gascotti seeds

HABITAT : The Weka frequents a variety of habitats and can be found from the coastline to above the tree-line. It frequents wetlands, scrub and grassland, beaches with rotting seaweed, tidal creeks and bays. Modified habitats including lawns, pastures, cultivated areas and plantations are frequented too. It favours low, dense vegetation providing cover. It may sometimes occur in urban environments. This species can be found from sea-level up to 1500 metres of elevation.

KNOW YOUR NEW ZEALAND BIRDS by Lynnette Moon – New Holland Publishers – ISBN: 1869660897.

Gruiformes Order – Rallidae Family.

The adult male has bulky body. The plumage is warm brown with conspicuous black streaks. The wings are short, but the tail is long for a flightless bird. The underparts are variably grey from chin to breast and belly, and the flanks are barred. The extent of this pattern may vary too. There are several variations in plumage colour according to subspecies and morphs. The head is brown streaked black, with broad grey supercilium, darker or paler depending on the race. The strong, pointed bill is pinkish-red with dark tip. The eyes are red, surrounded by two narrow, white crescents. The robust legs and feet are reddish.

The Weka has become a pest and a predator of endangered species such as birds, lizards and insects. It has been eradicated from some important conservation islands, in order to protect the other species.

Both sexes are similar in plumage, but the female is slightly smaller than the male, and her bill is paler at tip. The juvenile resembles adult of the same morph, but it is usually darker, except in the race “ hectori ”. The upperparts are less streaked. The underparts can be more uniform, with indistinct breast band. Flanks are mostly blotched, not barred. The bill is grey-black. The eyes are brown. Legs and feet are grey-brown.

SUBSPECIES AND RANGE : The Weka has four subspecies. G.a. greyi (not displayed) is found on North Island. This race has very dark plumage with large extent of grey on the underparts and little barring on flanks. The legs are dark.

G.a. scotti.

The Weka is monogamous like numerous Rallidae , and the pair-bonds are usually permanent. They are territorial throughout the year and solitary nesters. Calling is often increasing during the initiation of the breeding activity. The courtship behaviour is poorly known, but sexual display is relatively limited in this family. Some displays probably enhance the barred flanks, and courtship feeding and mutual preening are common.

REPRODUCTION OF THIS SPECIES : The Weka can breed all year round, but mainly from late winter to early summer. It nests on the ground, protected by the dense cover, or under logs, tussocks, rocks, and also in burrows or hollows in trees. The cup-shaped nest is made with woven grasses, twigs, moss and sedge leaves. It is lined with softer grasses or leaves, and feathers or wool when available. Both parents build the nest, or the male alone. Several sites within the territory can be used in several following years.

L’ENCYCLOPEDIE MONDIALE DES OISEAUX – Dr Christopher M. Perrins – BORDAS – ISBN: 2040185607.

Fr: Râle wéka Ang: Weka Maori: Weka All: Wekaralle Esp: Rascón Weka Ita: Rallo delle Filippine Nd: Weka Sd: Wekarall.

DESCRIPTION OF THE BIRD: Biometrics : Male length: 50-60 cm – Wingspan: 50-60 cm – Weight: 1050 g Female length: 46-50 cm – Weight: 737 g.

Adult and two juveniles.

The Weka is able to move over long distances, although being sedentary and flightless. It remains all year round in its territory, moving mainly to find better feeding areas. The subadult disperses after becoming independent, and may move over 9-10 kilometres. They can walk 4 km/day, and may swim very well, even crossing rivers and lakes. Some altitudinal movements are reported, and the birds also move from forests to open ground in summer.

David Nowell GALLERY.

Text by Nicole Bouglouan.

HANDBOOK OF THE BIRDS OF THE WORLD Vol 3 by Josep del Hoyo-Andrew Elliott-Jordi Sargatal – Lynx Edicions – ISBN : 8487334202.

Photographers :

G.a. scotti (displayed) is found on Stewart Island and adjacent small islands. This race is smaller than nominate.

G.a. australis (described and displayed) occurs in N and W South island.

Both races “ australis ” and “ scotti ” are very variable, with chestnut, grey and black morphs.

BEHAVIOUR IN THE WILD : The Weka is omnivorous and its diet is varied. It feeds on earthworms, larvae, slugs, snails, insects and their eggs, frogs and lizards, and spiders. It also takes crustaceans hidden among kelp on the beaches. This species is known to kill mice, rats and small rabbits. It also invades the nests of the ground-nesting birds where it takes the eggs and kills the chicks. Some vegetal food includes leaves, grass, berries, fallen fruits and seeds. It often scavenges food scraps at campsites, and it likes bright-coloured fruits and even takes shiny objects.

CALLS AND SONGS : SOUNDS BY XENO-CANTO The Weka’s usual call is a repeated “ee-wee” given with rising inflection. Other sounds such as loud, whistle-like calls can be heard. These calls are usually uttered at dawn and quickly after sunset. A territorial call, a characteristic “coo-eet” is produced as a duet by both mates. During territorial behaviour, and especially during aggressive encounters, they give booming calls “doon-doon-doon”. The contact call is a soft clucking.

Sources :

G.a. hectori (displayed) or “Buff Weka” was formerly found on E coast and interior of South Island, but it is now confined to the Chatham Islands where this race has been introduced. It is paler and mostly buff in colour.

The female lays 2-4 whitish to pale pink eggs with dark spots. Both adults incubate during 26-28 days, the female during the day and the male at night. At hatching, the chicks have brownish-black down, black bill, dark eyes and dark punkish-grey legs and feet.

Was wondering if anyone got the discounted 1/8s of kimbo kush at around 22%! I want to try it, but haven’t had gleaf since the herm issues and thought they might have this on sale because of that.

I've bought, and I haven't seen 100s of seeds. It's a great hi, imo. And at $45, nice price.

No idea brother. I picked up gascotti from gleaf once and it was fire no herm nothing smelled amazing. But every pick up since it has been herm. Kimbo, triabgle, spec ops to name a few. They tested very high and were super herm but it was still a good smoke. Sucks grinding up herm bud and you see 100s of baby seeds in the grinder.

and on the links between the parasite in its erythrocytic environment and the host. Two features are examined: the pathophysiology of malaria as an “inflammation”, and the possible initiating and maintaining factors involved. Attention is drawn to local and general responses in malaria which are similar to those which occur in inflammation and are demonstrable in bacterial infections and in malaria, babesiasis and other protozoan infections. Changes in endothelial permeability in malaria are next considered at some length, followed by statements on vasomotor changes in malaria in the hepatic, renal and intestinal circulations, which have been specially studied at the Liverpool School of Tropical Medicine. The kinin complex and other pharmacologically active agents are discussed fully, and it is shown that the kinin complex plays a significant part in disturbances that develop in permeable membranes, and is concerned with physiological change and resultant ultimate structural patterns. Another topic discussed is intravascular coagulation in malaria, the importance of which remains to be resolved in future research, one interesting region of which is the possible relationship between the peptide-peptidase which has been demonstrated in the kinin complex and the peptidase reactions involved in coagulation. Other topics discussed are anoxic anoxia (asphyxia), cytotoxic factors, and particularly mitochondria1 respiration inhibitors, and the physiological chain reaction which is set up and then leads to local or general disturbances that may be reversible but in time may become irreversible, leading to tissue death and the appearance of characteristic patterns of pathology. It is deemed helpful in visualizing the effects of a developing plasmodia1 infection to have this simple concept of initiating factors setting off a chain reaction of interlinked and interacting pathophysiological processes which may eventually involve changes in the local and general circulation of the blood, membrane permeability, hormone balance, and perhaps other as yet undisclosed effects. Klaus Rohde has not spared himself in writing the long review on the Aspidogastrea, especially Multicotyle purvisi Dawes, 1941. His researches on this trematode have occupied him throughout the last decade and it is noteworthy that we now know more about M . purvisi than we do about any other single aspidogastrid species. None of this research was completed when in 1961 I visited Kuala Lumpur as Examiner to the University of Malaya, and the review is of special interest to me because I described and proposed the erection of the new species and genus more than 30 years ago (Parasitology 33 (1 949, 300-3 15) from two well-preserved specimens collected on 25 July, 1932 from the river turtle Siebenrockiella crassicollis at Alor Star (north of Penang) by Mr G. B. Purvis, F.R.C.V.S., who was then serving as District Government Veterinary Surgeon in Malaya. I hasten to add that Klaus Rohde has given the name of this trematode fully not out of deference to any wish of mine but solely because of what I will call his teutonic insistence on precise delineation, and I am delighted to mention this record on the account of Mr G . B. Purvis. The review is divided into an introduction and eight other parts, which are subdivided. The introduction draws attention to the fact that the Aspidogastrea is the smallest of the three groups of Trematoda but of great interest because it shows a combination of the characters of Monogenea.

AII Rights Reserved No part of this book may be reproduced in any form by photostat, microfilm, or any other means, without written permission from the publishers Library of Congress Catalog Card Number: 62-22124 ISBN: 0-12-03 1710-9.

reminded that cestodes have been known since ancient times and also told that in recent years several reviews dealing with cestode diseases have appeared. Nevertheless, there have not been any recent reviews which deal in a comprehensive manner with infection by Taeniu suginuta. Therefore, these writers have tried to summarize all significant matters concerning this cestode and its cysticercus, i.e. nomenclature, host-relationships, structure and biology, clinical and therapeutic features, epidemiology and epizootology, and the prevention of infection. After a brief Introduction, they consider some taxonomic problems in one section and the hosts of T. saginata in another. Man appears to be the sole definitive host of the adult of this cestode species, but because larval cestodes are much less specific than corresponding adults, the list of intermediate hosts is long and constantly extending. Man may serve as intermediate host, 12 instances having been described, one in Chile concerned 59 patients, another in Rhodesia 62 patients. In India 450 instances of cysticercosis concerned soldiers, but T. saginata was not reported. A section of this review deals with structure and biology of the adult worm, egg, onchosphere and cysticercus in turn. One interesting point about the living adult tapeworm is that it is by no means passive but often moves against the peristaltic movements in the host’s intestines. The usual site seems to be the jejunum, but radiologists have found the worm in the terminal ileum, which is said to be the part best shown by radiological examination. The entire scolex and strobila has been recorded in several unusual locations such as the appendix and the gall bladder. The idea that the worm occurs singly has been refuted, although multiple infections occur in less than 1 % of cases, except in Mexico (nearly 573, but much greater infections have been observed in the southern republics of U.S.S.R. Many other interesting points arise in this part of the review. The number of eggs in one proglottis of T. saginata has been put at about 80,000, the daily output 720,000. Elsewhere the clinical aspects of taeniasis are dealt with in terms of symptomatology, clinical pathology, diagnosis and treatment, which cannot be considered here, except to say that there is much to interest clinicians. The matter of treatment by chemotherapy has been dealt with in two reviews during the 1960s, both from the Wellcome Research Laboratories, and they are detailed here. Yomesan is the drug of choice for T. saginata infection in Man at present and some suggestions are made for treatment with this and other drugs. A sixth section deals with epidemiology and concerns transmission between animals and man, a seventh with losses due to taeniasis and cysticercosis. These sections are very informative. It is stated that taeniasis and cysticercosis (T. saginata) are cosmopolitan in distribution and have become more prevalent in recent years. During the past 25 years the world population has increased by about 50% and that of cattle by about loo%, so that it is safe to assume that infections greatly exceed the 39 million estimated by Norman Stoll in 1947. Losses are difficult to estimate, because infection is rarely fatal, but some figures are available for European, African and American areas. Meat inspection is dealt with as a means of prevention, likewise serological diagnosis and the immunization of cattle. Sanitation is a matter discussed, its improvement, expensive but connected with higher standards of living.

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MYRONG. Scnurrz, Center for Disease Control, U S . Department of Health, Education and Welfare, Atlanta, Georgia, U.S.A. (p. 269)

LAIRD,Department of Biology, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada (p. 1)

Copyright @ 1972 by ACADEMIC PRESS INC. (LONDON) LTD.

*DONALD L. LEE,Houghton Poultry Research Station, Houghton, Huntingdon, England (p. 347)

ZBIGNIEW PAWLOWSKI, Clinic of Parasitic Diseases, Przybyszewskiego 49, Poznan, Poland (p. 269) C. PEARSON, Department of Parasitology, University of Queensland, St. Lucia, Brisbane 4067, Queensland, Australia (p. 153)

ACADEMIC PRESS INC. (LONDON) LTD. 24/28 Oval Road, London NWl United States Edition published by ACADEMIC PRESS INC. 111 Fifth Avenue New York, New York 10003.

PARASITOLOGY Edited by.

ACADEMIC PRESS London and New York.

PREFACE At the end of a decade and with ten volumes of Advances in Parasitology published I may be permitted to make an appraisal of a series of books which, because of a regular annual addition, has been regarded wrongly in some biological bibliographies as a scientific journal. Now that Volume 10 has appeared, 68 contributors have produced 57 original reviews and (since 1968) 15 short updated reviews, a vast summation of modern biological information and ideas in the field of parasitology. Thirty-one contributors lived in Great Britain, nine in Australia, ten in the U.S.A., six in Canada, three in Brazil, two each in Czechoslovakia, Poland, South Africa and Japan, and one in Israel. At my request, these writers found the time to record their thoughts and research experiences in well documented reviews. This may have cost innumerable man-hours, as have my editorial duties, but the benefit gained by stimulating teachers and researchers to greater effort in parasitology could hardly be reckoned in such units. Sixteen reviews deal with Protozoa, 13 with Trematoda, five with Cestoda and Acanthocephala, 12 with Nematoda, five with “helminths” and six with various parasitological topics. In the entire sequence of reviews, those on the Protozoa are concerned with avian and mammalian malaria, Chagas’ disease, coccidiosis, entamoebiasis, leishmaniasis, toxoplasmosis and trypanosomiasis. Trematode reviews are linked similarly with clonorchiasis, fascioliasis, paragonimiasis, paraimphistomiasis and schistosomiasis, cestode reviews with cysticercosis, echinococcosis and taeniasis, nematode reviews with ancylostomiasis, dracontiasis, filariasis, onchocercosis, parasitic bronchitis and trichiniasis. In vitro and in vivo culture of Protozoa come into the picture, and also similar methods of handling schistosomes and other trematodes and cestodes. There are reviews about snail vectors of trematodes and their control, about small but significant groups such as Aspidogastrea and Acanthocephala, about the evolution of parasites and their hosts, and about dynamic parasitic equilibrium in nematodes. There are reviews on larval Monogenea, on the life history sequence of digenetic trematodes and on intra-molluscan and intertrematode antagonism. There are reviews on parasitism and symbiosis in Turbellaria, on tissue reactions in the hosts of nematodes and on anthelmintic treatment and its results. Electronmicroscopy often comes into the picture and biochemistry plays some part in reviews. Much groundwork has been covered but it must be extended and many lacunae remain to be filled in. However, it is my hope to achieve much of this during another decade, if health permits. In the present volume, John R. Baker, Gordon F. Bennett, Glen Clark and Marshall Laird deal with what were once considered to be protozoan parasites of doubtful status and are here termed avian blood coccidians. They make a bold attempt to unravel tangled taxonomic confusion regarding two distinct groups of blood-dwelling stages of coccidia: (1) small non-pigmented nucleophilic parasites of mononuclear cells in the viscera and peripheral circulation; and (2) typical adeleine haemogregarines such as parasitize the vii.

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tKLAus ROHDE,Department of Parasitology, University of Queensland, St. Lucia, Brisbane 4067, Australia (p. 78)

ALEXANDER FLETCHER, Department of Tropical Medicine, Liverpool School of Tropical Medicine, Liverpool, England (pp. 31 and 49) DONALDHEYNEMAN, Hooper Foundation, University of California, San Francisco, California 94122, U.S.A. (p. 191)

BEN DAWES Professor Emeritus, University of London.

HOK-KAN LIM, Hooper Foundation, University of California, San Francisco, California 94122, U.S.A. (p. 191) Department of Tropical Medicine, Liverpool School of Tropical Medicine, Liverpool, England (pp. 3 1 and 49)

patterns are noted-rediae dominating sporocysts, predatory activity of rediae which feed upon sporocysts but may devour other larvae, e.g. mother rediae devouring daughter rediae or young cercariae. Redial morphology is considered carefully, the efficiency of predation and a triggering mechanism as well. Non-predatory effects are considered for both rediae and sporocysts as inhibitory or degenerative changes and possible mechanisms such as snail immunity, direct toxicity, and competition for nutrients or oxygen. An important section of the review is concerned with the parameters of intramolluscan inter-trematode antagonism. In the quest for a suitable antagonist against Schistosoma mansoni six species of echinostomes were tested in the laboratory, and Paryphostomum segregatum was the most effective. Consequently, much research was carried out on antagonism using the snail Biomphalaria glabrata, the trematode Schistosoma mansoni (target) and the echinostome Paryphostomum segregatum (predator). This model gave examples of miracidial penetration in either trematode species superimposed on the other species, the establishment of infection in B. glabrata, delayed redial migration, delayed germinal development within the redia, the attraction of predaceous rediae to sporocysts, the speed at which larval domination is completed and the unusual appearance of what appear to be third-generation sporocysts of S. mansoni. The phenomenon of trematode antagonism is then discussed in a separate section, in its relation to biological control. Trematode diseases such as fascioliasis and schistosomiasis have called forth the use of parasites, pathogens and predators of snails-protozoa, nematodes, leeches, fishes, ducks and geese-and reference is made to the discoveries with the molluscicide larvae of sciomyzid flies by C. 0. Berg (Advances in Parasitology 2 (1965), 259). Intramolluscan and inter-trematode antagonism is a new approach to biological control, and it is claimed that encouraging results so far obtained justify field trials against human schistosomes in endemic areas. Echinostomes are at present favoured for control of such trematode disease but other rediae-producing species must be isolated and tested, although trematode biocontrol may be applicable only in local or regional approaches. Success of control by trematode antagonism depends on strong infectivity of the antagonist in the snail that harbours the target species, and this entails heavy infection by a single miracidium in all ages of host snail in the full range of natural habitats, followed by rapid growth and development despite preceding trematode infection. It may therefore be that a single trematode species cannot be so adaptive and powerful an antagonist as to serve in biological control in other than endemic areas where it is already adapted to local snails. A plea is made therefore to develop trematode biocontrol locally. The snail is the limiting environment, imposing real barriers to a newly-introduced trematode species. Once inside the snail and successfully multiplying it is not unlikely that the antagonist would dispatch the prey trematode. Much that cannot be mentioned here is discussed in this review and in a summary the point is made that this formof biocontrol “offers limited but possibly important usefulness, especially if teamed with other control methods, such as molluscicide, sanitary and therapeutic”. In the review by Zbigniew Pawlowski and Myron G. Schultz we are.

* Author in the section “Short Review” Present address: Department of Pure and Applied Zoology, University of Leeds, Leeds, England. t Present address: Department of Zoology, University of Khartoum, Sudan.

GLENW. CLARK, Department of Biological Sciences, Central Washington State College, Ellensburg, Washington, U.S.A. (p. 1)

Advances in PARASITOLOGY.

details what he considers to be the “singular features” of digenetic life cycles, adding what he believes any scheme of phylogeny should take into consideration, namely, alternation of generations, alternation of molluscan and piscine hosts, the existence of a tailed larva (the cercariae) and methods of transfer that include penetration of the free-swimming miracidium into some snail, the escape from the snail in many instances, and the ingestion of a cercarial or metacercarial stage by a definitive host, except in schistosomes. He is generous in his comments about these minimal considerations before passing on to his detailed scheme. After considering the adoption of parasitism and a one-host cycle, he goes on to deal in turn with the origin of an alternation of generations, the addition of a vertebrate host and a redial generation in the parasite, the addition of a metacercarial stage, the acquisition of a second intermediate host and the three-host cycle and its modifications. He then notes phylogenetic implications and summarizes his findings. In order to explain the “ubiquity” of the cercaria he postulates that the present first intermediate host was the original host of the proto-digenean and that escape from this host is primitive. To explain the occurrence in many life cycles of a free-swimming miracidium he further postulates that the proto-digenean was an ectoparasite of the molluscan host. Assuming that it became a visceral parasite that escaped from the host as an adult in order to lay its eggs, he indicates that the known life cycles of contemporary Digenea may be interpreted in an order of acquisition of hosts as follows: vertebrate definitive (two-host cycle) and invertebrate second intermediate (three-host cycle). More than this it is not necessary to state here, except that the three-host cycle is the commoner and has arisen several times over from two-host cycles, and has been secondarily reduced in some groups of the Digenea through loss of the definitive host or of the second intermediate host, or possibly the loss of both hosts. There are no simple cycles amongst the Digenea and speculation is hypothetical but this thoughtful effort by John Pearson will help us to classify the multifarious life cycles and also point the way to further study in other and future researches. The review by Hok-Kan Lim and Donald Heyneman is concerned with intramolluscan inter-trematode antagonism. It has been known for some years that echinostome larvae within a snail host may inhibit and disrupt or prevent the development of other trematode larvae but only recently was this phenomenon demonstrated in laboratory experiments carried out in San Francisco and Kuala Lumpur, Malaya, basically to study single or double trematode infections within a molluscan host. After an Introduction, Lim and Heyneman give much information about the maintenance of certain snails and trematodes, mainly the snail Biomphalaria glabrata and the trematodes Paryphostomum segregatum (an echinostome) maintained as adults in a Brazilian black vulture (uruba) and Schistosoma mansoni, maintained as adults in the golden hamster. The term direct antagonism was used to denote predatory or physical activities by rediae on other trematode larvae within the snail. By study and analysis it was hoped to recognize, evaluate and “quantitate” the conditions that predispose one trematode to dominate another trematode within the same snail. Various trematode interaction.

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blood cells of vertebrates during the course of the life cycle. Publications on avian blood coccidians of both groups of parasites are listed chronologically in Table I and a check-list of avian hosts of both groups of parasites is given in Table 11.These parasites are considered in separate sections as atoxoplasms and adeleine haemogregarines. It is unnecessary here to follow the detailed discussions of this team of professional protozoologists, who also give in Table I11 a classified host-list indicating atoxoplasm materials in thin Giemsastained blood films which are available for study in the WHO International Reference Centre for Avian Malaria Parasites at the Memorial University of Newfoundland. That there has been much confusion about the taxonomic status of these enigmatical blood parasites of birds is evident to the reader and the summarized information presented provides, in the words of the authors, “a fascinating basis for speculation”, and also “suggests hypotheses meriting early testing” by controlled experimentation to determine the true nature of atoxoplasms, and whether or not all atoxoplasms belong to the genus Zsospora and belong to one or more than one widespread species. Another point of wonderment is whether or not the few records of adeleine haemogregarines from birds represent simply accidental infection with parasites of reptiles which share the avian host environment. Alexander Fletcher and Brian Maegraith have not attempted to write a comprehensive review of literature on the metabolism of the malaria parasite but instead discuss some considerations and some current resarch trends which seem to advance our knowledge of fundamental biochemical processes which occur in parasites and are involved in the host-parasite relationship. After making some general considerations about the hazards presented by most types of cell preparation, they focus attention on the pentose phosphate pathway (PPP), for which the malaria parasite could have an absolute requirement, because it is probably the principal pathway for the production of pentose sugars necessary for nucleic acid synthesis. There is now evidence that most of the malaria parasites studied up to the present are dependent on the glucose-6-phosphate dehydrogenase (G-CPD), the initial enzyme of the PPP, the parasites being unlikely to thrive in enzyme-deficient cells and thus unable to produce an overwhelming infection. Further metabolism remains enigmatical, but current trends in research with mammalian species are discussed. Other topics considered are carbon dioxide fixation by malaria parasites, aerobic mechanisms, and the metabolism of chloroquine-resistant malaria parasites. These writers then turn to consider the metabolism of the host during infection, namely biological changes in erythrocytes, the effects of acute infection on host-tissue metabolism and host lipid metabolism. Such studies are enabling some advances to be made in our understanding of the pathological process involved in malaria. In another review Brian Maegraith and Alexander Fletcher concern themselves with the pathogenesis of malaria and they commence by indicating that the hypothesis of the physiopathological pattern of malaria is essentially inflammatory and non-specific in nature has long been upheld and is substantially correct. Research has been applied mainly on the effects of malaria infection on vascular membranes and vasomotor mechanisms of the host.

CONTRIBUTORS TO VOLUME 10 JOHNR. BAKER,Molten0 Institute, University of Cambridge, England (p. 1) GORDON F. BENNETT,Department of Biology, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada (p. 1)

and Digenea and contains forms ill-adapted to a parasitic mode of life and likely therefore to throw some light on the origin of parasitism in the flatworms. One section deals with general characters and leads on to another section giving a very detailed account of adult structure under the headings of tegument, digestive tract, protonephridial, genital and nervous systems, receptors and details of the characteristic ventral adhesive disc occupying most of the ventral part of the body. Rohde prefers to call the outermost layer of the body the “tegument”, which other writers designate by other names; the essential point is that it is not a hard resistant cuticle as once supposed but a cytoplasmic layer of much greater complexity, as revealed by electron-microscopy. It contains mitochondria and ovoid bodies, in some areas vacuoles and lamellated bodies, and the surface membrane forms elevations between which there is a mucoid layer of variable thickness. In some areas rib-like elevations of the surface support a thick mucoid layer consisting of a reticulum of fibres with electron dense bodies of various sizes. This “tegument” is syncytial, and apparently it is not formed by fusion of epithelial cells in M . purvisi but originates in its definitive form. Other organs of the adult-digestive tract, protonephridial, genital and nervous systemshave their structures elucidated with the help of the electron-microscope, and the details of the nervous system are revealed in their exquisite complexity. The sensory receptors are more complex and varied than has generally been supposed, and much more numerous. The structure of the free-living larva is described in the same thorough manner, in terms relating to general structure, tegument and ciliated tufts, glands and caudal appendage, digestive protonephridial and nervous systems, and sense receptors. As far as possible the details are integrated with what is known about other aspidogastrid larvae. Development is then considered in terms of the egg, cleavage and larval development, hatching, development of the parasitic stage and relative (allometric) growth. The portrayal of changing relative size in various organs during growth approaches and surpasses what I first attempted more than 30 years ago for Styphlodora elegans Dawes, 1941 (Parasitology, 33 (1941), 445-458) and more recently for Fasciola hepatica (J. Helminthology 36 (1962), 11-38). The biology of aspidogastrids is closely considered in respect of life span, behaviour and infectivity of free larvae, route of invasion in the mollusc, localization and sexual maturation in the intermediate host, infectivity in the vertebrate host and growth, localization in this host and specificity of infection, with some information on the survival of adult forms outside this host. Rohde then discussed the phylogenetic position of the Aspidogastrea, which have some archaic features. Reasons are given for placing aspidogastrids in a separate group, and for believing that they are closely related to the Digenea. An attempt is made to derive the digenetic life cycle from that of the aspidogastrid and to discuss some unresolved problems. It is likely that many parasitologists will agree that Rohde’s review greatly enhances our knowledge of trematode structure development and biology. John C . Pearson has chosen to write on a phylogeny of life cycle patterns of digenetic trematodes, a theme that has long invited speculation. After an Introduction giving details of earlier ideas and some recent views, this writer.

The solitary updated review by Donald L. Lee lays emphasis on new work rather than on research that does not break new ground, and much more space is now devoted to the outer coverings of larval helminths and the development of this covering in adults. The following groups and species are considered : Turbellaria (Kronborgia amphipodicola) ; Monogenea (various species); Digenea (Fasciola hepatica and various other species); Cestodaria (Gyrocotyle urna) ; Cestoda (various species) ; Nematoda (various species); Acanthocephala (Polymorphus minutus). A summary is provided. At the end of one decade and the beginning of another I am happy once more to express my gratitude to friends and colleagues who have worked hard and long at compiling these reviews and who have helped to produce what I referred to above as a vast summation of modern biological information and ideas in the field of parasitology. I
am equally pleased to thank the staff of Academic Press who have ironed out innumerable difficulties and smoothly brought out the tenth volume in this series, and to hope that our cooperation can continue far into a second decade, to say the least. “Rodenhurst” 22 Meadow Close* Reedley Drive REEDLEY, Nr Burnley Lancs BBlO 2QU England.