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Problems concerned with gametogenesis in Haemosporidiidea, with particular reference to the genus Plasmodium

Published online by Cambridge University Press:  06 April 2009

Ann Bishop
Affiliation:
Molteno Institute, University of Cambridge

Extract

Although many interesting observations have been made upon gametogenesis in Haemosporidiidea many fundamental problems await solution. Our knowledge of the nuclear changes occurring during the development of the gametes and the fertilization of the female gamete is still incomplete. Little is known of the factors which control gametocyte production, though there is evidence that in some species, i.e. Leucocytozoon simondi and Haemoproteus columbae in the duck, it is influenced by the physiological stage of the host. The type of host and the method of transmission have also been shown to affect the numbers of gametocytes formed in some species. No correlation has been found in Plasmodium, the genus in which this subject has been studied extensively, between acquired immunity and gametocyte formation. Although a broad relationship has been demonstrated in Plasmodium between the density of gametocytes in the blood and the oocyst rate and density assessed in susceptible mosquitoes, hosts heavily infected with apparently ripe gametocytes may prove non-infective to susceptible mosquitoes. In birds heavily infected with P. gallinaceum, serum taken at the peak of parasitaemia has been shown to affect adversely the infectivity of gametocytes to mosquitoes. Pamaquin and primaquine, in small doses, inhibit the development of gametocytes completely, whereas proguanil may not prevent the formation of oocysts though it inhibits their subsequent development. High densities of gametocytes have been observed in patients treated with proguanil or sulphamethazine. An actual in crease in the number of gametocytes produced, as compared with the untreated control strain, was observed in strains of P. gallinaceum in process of developing resistance to sulphadiazine, proguanil or 2:4-diamino-6:7-diisopropylpteridine as a result of treatment with those drugs.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1955

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References

REFERENCES

Adler, S. & Tchernomoretz, I. (1943). The extra-erythrocytic origin of gametocytes of Plasmodium gallinaceum Brumpt, 1935. Ann. Trop. Med. Parasit. 37, 148.Google Scholar
Barber, M. A., Komp, W. H. W. & Newman, B. M. (1929). The effect of small doses of plasmochin on the viability of gametocytes of malaria as measured by mosquito infections. Publ. Hlth Rep., Wash., 44, 1409.Google Scholar
Barzilai-Vivaldi, G. & Kauders, O. (1924). Die Impf-Malaria—experimentall durch Anophelen nicht übertragbar. Wien. klin. Wschr. 37, 1055.Google Scholar
Bastianelli, G. & Bignami, A. (1900 a). Ueber die structur der Malariaparasiten insbesondere der Gameten der Parasiten des Aestivoautumnal fiebers. Untersuch. Naturl. Mensch. Tiere, 17, 108.Google Scholar
Bastianelli, G. & Bignami, A. (1900 b). Ueber die Entwickelung der Parasiten der Terzana im Anopheles claviger. Untersuch. Naturl. Mensch. Tiere, 17, 147.Google Scholar
Bieniarz, J. (1950). Influence of vertebrate gonadotrophic hormones upon the reproductive cycle of certain protozoa in frogs. Nature, Lond., 165, 650.CrossRefGoogle Scholar
Bishop, A. & Birkett, B. (1948). Drug-resistance in Plasmodium gallinaceum, and the persistence of paludrine-resistance after mosquito transmission. Parasitology, 39, 126.Google Scholar
Bishop, A. (1943). Variation in gametocyte production in a strain of Plasmodium relictum in canaries. Parasitology, 35, 82.Google Scholar
Bishop, A. (1954). The effect of sulphadiazine, proguanil and 2:4-diamino-6:7-diisopropyl-pteridine upon gametocyte production in Plasmodium gallinaceum (Brumpt, 1935). Parasitology, 44, 120.CrossRefGoogle Scholar
Black, R. H. (1946). The effect of anti-malarial drugs on Plasmodium falciparum (New Guinea strains) developing in vitro. Trans. R. Soc. Trop. Med. Hyg. 40, 163.Google Scholar
Boivin, A., Vendrely, R. & Vendrely, C. (1948). L'acide désoxyribonucléique du noyau cellulaire, dépositaire des caractères héréditaires; arguments d'ordre analytique. C.R. Acad. Sci., Paris, 226, 1061.Google Scholar
Boyd, M. F. (1935). On the schizogonous cycle of Plasmodium vivax, Grassi and Feletti. Amer. J. Trop. Med. 15, 605.CrossRefGoogle Scholar
Boyd, M. F. (1942). On the varying infectiousness of different patients infected with vivax malaria. Amer. J. Trop. Med. 22, 73.Google Scholar
Boyd, M. F. (1945). On difficulties arising in the experimental propagation of falciparum malaria. Amer. J. Trop. Med. 25, 293.Google Scholar
Boyd, M. F. (1949). Malariology. A Comprehensive Survey of all Aspects of this Group of Diseases from a Global Standpoint. p. 611. Philadelphia and London: W. B. Saunders and Co.Google Scholar
Boyd, M. F., Stratman-Thomas, W. K. & Muench, H. (1936). The occurrence of gametocytes of Plasmodium vivax during the primary attack. Amer. J. Trop. Med. 16, 133.Google Scholar
Bruce-Chwatt, L. J. (1951). Malaria in Nigeria. Bull. World Hlth Org. 4, 301.Google Scholar
Calkins, G. N. & Bowling, R. C. (1926). Gametic meiosis in Monocystis. Biol. Bull., Woods Hole, 51, 385.Google Scholar
Cantrell, W. & Jordan, H. B. (1946). Changes in the infectiousness of gametocytes during the course of Plasmodium gallinaceum infections. J. Infect. Dis. 78, 153.CrossRefGoogle Scholar
Chen, T. T. (1944). The nuclei of avian malaria parasites. 1. The structure of nuclei in Plasmodium elongatum with some considerations of technique. Amer. J. Hyg. 40, 26.Google Scholar
Chernin, E. (1952). The relapse phenomenon in the Leucocytozoon simondi infection of the domestic duck. Amer. J. Hyg. 56, 101.Google Scholar
Christophers, S. R. (1924). The mechanism of immunity against malaria in communities living under hyperendemic conditions. Indian J. Med. Res. 12, 273.Google Scholar
Cleveland, L. R. (1949). Hormone-induced sexual cycles of flagellates. I. Gametogenesis, fertilization, and meiosis in Trichonympha. J. Morph. 85, 187.Google Scholar
Corradetti, A. (1936). Osservazioni sul ciclo schizogonico del Plasmodium vivax. Riv. Malarial. 15, 14.Google Scholar
Cuboni, E. (1926). Gametenfreie Plasmodium vivax-Stämme. Wien. klin. Wschr. 39, 1475.Google Scholar
Danilewsky, B. (1885). Zur Parasitologie des Blutes. Biol. Zbl. 5, 529.Google Scholar
Danilewsky, B. (1889). La parasitologie comparée du sang. I. Nouvelles recherches sur les parasites du sang des oiseaux. Kharkoff.Google Scholar
Deane, H. W. (1945). Studies on malarial parasites. II. The staining of two primate parasites by the Feulgen technique. J. Cell. Comp. Physiol. 26, 139.Google Scholar
Dobell, C. (1925). The life history and chromosome cycle of Aggregata eberthi (Protozoa: Sporozoa: Coccidia). Parasitology, 17, 1.Google Scholar
Dobell, C. & Jameson, A. P. (1915). The chromosome cycle in coccidia and gregarines. Proc. Roy. Soc. B, 89, 83.Google Scholar
Downs, W. G. (1947). Infections of chicks with single parasites of Plasmodium gallinaceum Brumpt. Amer. J. Hyg. 46, 41.Google Scholar
Draper, C. C. (1953). Observations on the infectiousness of gametocytes in hyperendemic malaria. Trans. R. Soc. Trop. Med. Hyg. 47, 160.Google Scholar
Eyles, D. E. (1951). Studies on Plasmodium gallinaceum. I. Characteristics of the infection in the mosquito, Aëdes aegypti. Amer. J. Hyg. 51, 101.Google Scholar
Eyles, D. E. (1952). Studies on Plasmodium gallinaceum. III. Factors associated with the malaria infection in the vertebrate host which influence the degree of infection in the mosquito. Amer. J. Hyg. 55, 386.Google Scholar
Fairley, N. H. (1946). Researches on Paludrine (M. 4888) in malaria. An experimental investigation undertaken by the L.H.Q. medical research unit (A.I.F.), Cairns, Australia. Trans. R. Soc. Trop. Med. Hyg. 40, 105.Google Scholar
Findlay, G. M., Maegraith, B. G., Markson, J. L. & Holden, J. R. (1946). Investigations in the chemotherapy of malaria in West Africa. V. Sulphonamide compounds. Ann. Trop. Med. Parasit. 40, 358.CrossRefGoogle Scholar
Gambrell, W. E. (1937). Variation in gametocyte production in avian malaria. Amer. J. Trop. Med. 17, 689.CrossRefGoogle Scholar
Garnham, P. C. C. (1931). Observations on Plasmodium falciparum with special reference to the production of crescents. Kenya E. Afr. Med. J. 8, 2.Google Scholar
Grassi, B. (1900). Studi di uno Zoologo sulla malaria. Mem. Accad. Lincei (5) 3, 299.Google Scholar
Green, R. (1929). Observations on some factors influencing the infectivity of malarial gamete carriers in Malaya to Anopheles maculatus. Bull. Inst. Med. Res. F.M.S. 5, 41.Google Scholar
Guyénot, E. & Ponse, K. (1926). Une microsporidie, Plistophora bufonis, parasite de l'organe de Bidder du Crapaud. Rev. suisse Zool. 33, 213.Google Scholar
Hewitt, R. I. & Richardson, A. P. (1943). The direct plasmodicidal effect of quinine, atabrine and plasmochin on Plasmodium lophurae. J. Infect. Dis. 73, 1.CrossRefGoogle Scholar
Huff, C. G. (1927). Studies on the infectivity of plasmodia of birds for mosquitoes, with special reference to the problem of immunity in the mosquito. Amer. J. Hyg. 7, 706.Google Scholar
Huff, C. G. (1941). Comparisons of a clon of Plasmodium cathemerium with its parent strain and with two strains derived from the clon by mosquito transmission. J. Infect. Dis. 68, 184.Google Scholar
Huff, C. G. (1942). Schizogony and gametocyte development in Leucocytozoon simondi, and comparisons with Plasmodium and Haemoproteus. J. Infect. Dis. 71, 18.Google Scholar
Huff, C. G. & Coulston, F. (1946). The relation of natural and acquired immunity of various avian hosts to the cryptozoites and metacryptozoites of Plasmodium gallinaceum and Plasmodium relictum. J. Infect. Dis. 78, 99.CrossRefGoogle Scholar
Huff, C. G. & Gambrell, E. (1934). Strains of Plasmodium cathemerium with and without gametocytes. Amer. J. Hyg. 19, 404.Google Scholar
James, S. P. (1931). Some general results of a study of induced malaria in England. Trans. R. Soc. Trop. Med. Hyg. 24, 477.Google Scholar
James, S. P., Nicol, W. R. & Shute, P. G. (1936). Clinical and parasitological observations on induced malaria. Proc. R. Soc. Med. 29, 879.Google Scholar
Jameson, A. P. (1920). The chromosome cycle of gregarines, with special reference to Diplocyctis schneideri Kunstler. Quart. J. Micr. Sci. 64, 207.Google Scholar
Jeffery, G. M. (1951). Observations on a gametocyteless strain of Plasmodium falciparum. J. Nat. Malar. Soc. 10, 337Google Scholar
Jírovec, O. & Ĉerný, W. (1932). Die Ergebnisse der Nuklealreaktion bei Vogelmalaria. Zbl. Bakt. (Orig.), 126, 181.Google Scholar
Kligler, I. J. & Mer, G. (1937). Studies on the effect of various factors on the infection rate of Anopheles elutus with different species of Plasmodium. Ann. Trop. Med. Parasit. 31, 71.Google Scholar
Knowles, R. & Basu, B. C. (1943). Laboratory studies on the infectivity of Anopheles stephensi. J. Malar. Inst. India, 5, 1.Google Scholar
Koch, R. (1899 a). Ergebnisse der wissenshaftlichen Expedition des Geheimen Medicinalraths Professor Dr Koch nach Italien zur Erforschung der Malaria. Dtsch. med. Wschr. 69.Google Scholar
Koch, R. (1899 b). Ueber die Entwicklung der Malariaparasiten. Z. Hyg. InfektKr. 33, 1.Google Scholar
Laveran, A. (1881). Description d'un nouveau parasite découvert dans le sang des malades attéints d'impaludisme. C.R. Soc. Biol., Paris, 93, 627.Google Scholar
Léger, L. & Duboscq, O. (1909). Etudes sur la sexualité chez les grégarines. Arch. Protistenk. 17, 19.Google Scholar
Lewert, R. M. (1950). Alterations in the cycle of Plasmodium gallinaceum following passage through tissue culture. II. The behaviour of the strain during multiple passage through chicks. Amer. J. Hyg. 51, 178.Google Scholar
Lewert, R. M. (1952). Nucleic acids in plasmodia and the phosphorus partition of cells infected with Plasmodium gallinaceum. J. Infect. Dis. 91, 125.Google Scholar
Lüdicke, M. & Piekarski, G. (1952). Über die Gametenbildung von Plasmodium falciparum (Welch 1897). Zbl. Bakt. (Orig.), 157, 522.Google Scholar
Lumsden, W. H. R. & Bertram, D. S. (1940). Observations on the biology of Plasmodium gallinaceum Brumpt. 1935, in the domestic fowl, with special reference to the production of gametocytes and their development in Aëdes aegypti (L). Ann. Trop. Med. Parasit. 34, 135.Google Scholar
Lwoff, A. & Valentini, S. (1948). Culture du flagellé opalinide Cepedea dimidiata. Ann. Inst. Pasteur, 75, 1.Google Scholar
MacCallum, W. G. (1898). On the haematozoan infections of birds. J. Exp. Med. 3, 117.Google Scholar
MacDougall, M. S. (1947). Cytological studies of Plasmodium: the male gamete. J. Nat. Malar. Soc. 6, 91.Google Scholar
McFadzean, J. A. (1951). Morphological changes in Plasmodium cynomolgi following proguanil, sulphadiazine, and mepacrine therapy. Trans. R. Soc. Trap. Med. Hyg. 44, 707.Google Scholar
McGhee, R. B. (1951). The adaptation of the avian malaria parasite Plasmodium lophurae to a continuous existence in infant mice. J. Infect. Dis. 88, 86.Google Scholar
Mackerras, M. J. & Ercole, Q. N. (1948). Observations on the action of paludrine on malarial parasites. Trans. R. Soc. Trap. Med. Hyg. 41, 365.Google Scholar
Mackerras, M. J. & Ercole, Q. N. (1949 a). Some observations on the action of quinine, atebrin, and plasmoquine on Plasmodium vivax. Trans. R. Soc. Trap. Med. Hyg. 42, 443.CrossRefGoogle ScholarPubMed
Mackerras, M. J. & Ercole, Q. N. (1949 b). Observations on the action of quinine, atebrin and plasmoquine on the gametocytes of Plasmodium falciparum. Trans. R. Soc. Trop. Med. Hyg. 42, 455.Google Scholar
Maegraith, B. G., Adams, A. R. D., King, J. D., Townshend, R. H., Davey, T. H. & Havard, R. E. (1945). Studies on synthetic antimalarial drugs. XIV. Results of a preliminary investigation of the therapeutic action of 4888 (paludrine) on acute attacks of malignant tertian malaria. Ann. Trop. Med. Parasit. 39, 232.Google Scholar
Manson, P. (1894). On the nature and significance of the crescentic and flagellated bodies in malarial blood. Brit. Med. J. ii, 1306.Google Scholar
Manson, P. (1896). The life-history of the malaria germ outside the human body. Lancet, i, 831.Google Scholar
Manson, P. (1898). The mosquito and the malaria parasite. Brit. med. J. ii. 849.Google Scholar
Manwell, R. D. (1943). Malaria infections by four species of Plasmodium in the duck and chicken, and resulting parasite modification. Amer. J. Hyg. 38, 211.Google Scholar
Micks, D. W. (1947). A loss of gametocytes in Plasmodium elongatum. J. Parasit. 33, 499.Google Scholar
Mudrow-Reichenow, L. (1953). Die gametozide Wirkung des Primaquine im Tierversuch verglichen mit Plasmochin. Z. Tropenmed. u. Parasit. 4, 161.Google Scholar
Mühlens, P. (1926). Die Behandlung der natürlichen menschlichen Malaria-Infektion mit Plasmochin. Naturwissenschaften, 14, 1154.Google Scholar
Mühlens, P. & Kirschbaum, W. (1924). Weitere parasitologische Beobachtungen bei künstlichen Malariainfektionen von Paralytikern. Arch. Schiffs-u. Tropenhyg. 28, 131.Google Scholar
Muirhead-Thomson, R. C. (1954 a). Low gametocyte thresholds of infection of Anopheles with Plasmodium falciparum. A significant factor in malaria epidemiology. Brit. Med. J. i, 68.Google Scholar
Muirhead-Thomson, R. C. (1954 b). Factors determining the true reservoir of infection of Plasmodium falciparum and Wuchereria bancrofti in a West African village. Trans. R. Soc. Trap. Med. Hyg. 48, 208.Google Scholar
Muirhead-Thomson, R. C. & Mercier, E. C. (1952). Factors in malaria transmission by Anopheles albimanus in Jamaica. Ann. Trop. Med. Parasit. 46, 103.Google Scholar
Mulsow, K. (1911). Über Fortpflanzerungserscheinungen bei Monocystis rostrata n.sp. Arch. Protistenk. 22, 20.Google Scholar
Nabih, A. (1938). Studien über die Gattung Klossia und Beschreibung des Lebenszyklus von Klossia loosi (nov.sp.). Arch. Protistenk. 91, 474.Google Scholar
Naville, A. (1927 a). Recherches sur le cycle évolutif et chromosomique de Klossia helicina (A. Schneider). Arch. Protistenk. 57, 427.Google Scholar
Naville, A. (1927 b). Le cycle chromosomique et la meiose chez les monocystis. Z. Zellforsch. 6, 257.Google Scholar
Naville, A. (1927 c). Le cycle chromosomique d' Urospora lagidis (de Saint Joseph). Parasitology, 19, 100.CrossRefGoogle Scholar
Naville, A. (1930). Recherches cytologiques sur les schizogrégarines. I. Le cycle évolutif de Mattesia dispora n.g., n.sp. Z. Zellforsch. 11, 375.Google Scholar
Opie, E. L. (1898). On the haemocytozoa of birds. J. Exp. Med. 3, 79.Google Scholar
Paehler, F. (1904). Ueber die Morphologie, Fortpflanzung und Entwicklung von Gregarina ovata. Arch. Protistenk. 4, 64.Google Scholar
Patten, R. (1935). The life history of Merocystis kathae in the whelk, Buccinum undatum. Parasitology, 27, 399.Google Scholar
Phillips, N. E. & Mackinnon, D. L. (1946). Observations on a monooystid gregarine, Apolocystis elongata n.sp., in the seminal vesicles of Eisenia foetida (Sav.). Parasitology, 37, 65.Google Scholar
Plehn, A. (1925). Beobachtungen bei Paralytikermalaria. Arch.Schiffs.-U. Tropenhyg. 29, 56.Google Scholar
Ramakrishnan, S. P., Young, M. D., Jeffery, G. M., Burgess, B. W. & McLendon, S. B. (1952). The effect of single and multiple doses of paludrine upon Plasmodium falciparum. Amer. J. Hyg. 55, 239.Google Scholar
Reichenow, E. (1921). Die Hämococcidien der Eidechsen. Vorbemerkungen und I Teil: Die Entwicklungsgeschichte von Karyolysus. Arch. Protistenk. 42, 179.Google Scholar
Robertson, J. D. (1945). Notes on gametocyte threshold for infection of Anopheles gambiae Giles, 1902, and Anopheles melas Theobald, 1903, in West Africa. Ann. Trop. Med. Parasit. 39, 8.Google Scholar
Roehl, W. (1927). Über Plasmochinbehandlung der natürlichen Malaria. Arch. Schiffs- u. TropenHyg. 31, Beiheft I, 48.Google Scholar
Ross, R. (1897). On some peculiar pigmented cells found in two mosquitoes fed on malarial blood. Brit. Med. J. ii, 1786.Google Scholar
Ross, R. (1898 a), Report on the cultivation of Proteosoma, Labbé, in grey mosquitoes. Indian Med. Gaz. 33, 401.Google Scholar
Ross, R. (1898 b). Report on the cultivation of Proteosoma, Labbé, in Grey Mosquitoes. Calcutta. India: Office of the Superintendent of Government Printing. 21 May 1898.Google Scholar
Ross, R. (1898 c). Preliminary Report on the Infection of Birds with Proteosoma by the bites of Mosquitoes. G.C. Press, Simla. 27 October 1898.Google Scholar
Sakharoff, M. N. (1893). Recherches sur les hématozoaires des oiseaux. Ann. Inst. Pasteur, 7, 801.Google Scholar
Sautet, J. (1953). L'indice de régression au cours de la lutte antipaludique. Bull. Soc. Pat. exot. 46, 510.Google Scholar
Schaudinn, F. (1902). Studien über krankheitserregende Protozoen. II. Plasmodium vivax (Grassi & Feletti) der Erreger des Tertianfiebers beim Menschen. Arb. GesundhAmt., Berl., 19, 169.Google Scholar
Schnitzler, H. (1905). Ueber die Fortpflanzung von Clepsidrina ovata. Arch. Protistenk. 6, 309.Google Scholar
Schüffner, W. A. P. (1919, 1938). Two subjects relating to the epidemiology of malaria. (Translation by Swellengrebel of paper published in Mededeelingen van den Burgerilijken Geneeskundigen Dienst in Nederlandsch-Indie. 1919). J. Malar. Inst. India. 1, 221.Google Scholar
Schulze, (1925). Die Malariabehandlung der Paralyse. Dtsch. med. Wshr. 51, 1856.Google Scholar
Shah, K. S. (1934). The periodic development of sexual forms of Plasmodium cathemerium in the peripheral circulation of canaries. Amer. J. Hyg. 19, 392.Google Scholar
Shah, K. S., Rozeboom, L. E. & Rosario, F. del. (1934). Studies on the infectivity of Plasmodium cathemerium of canaries for mosquitoes. Amer. J. Hyg. 20, 502.Google Scholar
Shute, P. G. & Maryon, M. (1948). The gametocytocidal action of paludrine upon infections of Plasmodium falciparum. Parasitology, 38, 264.Google Scholar
Shute, P. G. & Maryon, M. (1951). A study of gametocytes in a West African strain of Plasmodium falciparum. Trans. R. Soc. Trop. Med. Hyg. 44, 421.Google Scholar
Sinton, J. A., Baily, J. D. & Chaud, D. (1926). Studies in malaria with special reference to treatment. Part IV. The occurrence of sexual forms of Plasmodium falciparum in the peripheral circulation. Indian J. Med. Res. 13, 895.Google Scholar
Srivastava, R. S., Chakrabarti, A. K. & Mukherjee, S. K. (1953). Therapeutic trial of pyrimethamine (daraprim) in human malaria. Indian J. Malar. 7, 5.Google Scholar
Swellengrebel, H. N. & Swellengrebel de Gbaaf, J. M. H. (1920). Studies on the various types of malarial infection and the effect of quinine treatment thereon amongst the native population of the Malay archipelago. Ann. trap. Med. Parasit. 14, 41.CrossRefGoogle Scholar
Taliaferro, W. H. & Taliaferro, W. H. (1934). The transmission of Plasmodium falciparum to the howler monkey, Alouatta sp. I. General nature of the infections and morphology of the parasites. II. Cellular reactions. Amer. J. Hyg. 19, 318.Google Scholar
Thompson, P. E. & Huff, C. G. (1944). A saurian malarial parasite, Plasmodium mexicanum n.sp., with both elongatum- and gallinaceum- types of exoerythrocytic stages. J. Infect. Dis. 74, 48.CrossRefGoogle Scholar
Thurston, J. P. (1951). Morphological changes in Plasmodium berghei following proguanil, sulphadiazine and mepacrine therapy. Trans. R. Soc. Trap. Med. Hyg. 44, 703.Google Scholar
Thurston, J. (1953). The morphology of Plasmodium berghei before and after treatment with drugs. Trans. R. Soc. Trap. Med. Hyg. 47, 248.Google Scholar
Valkanov, A. (1935). Untersuchungen über den Bntwicklungskreis eines Turbellarienparasiten (Monocystella Arndti). Z. Parasitenk. 7, 517.Google Scholar
Vendrely, R. & Vendrely, C. (1949). Nouveaux résultats sur la teneur absolue en acide désoxyribonucléique du noyau cellulaire. Cas particulier des erythrocytes d'oiseau. C.R. Acad. Sci., Paris, 228, 1256.Google Scholar
Vendrely, R. & Vendrely, C. (1950). Sur la teneur absolue en acide désoxyribonucléique du noyau cellulaire chez quelques espèces d'oiseaux et de poissons. C.R. Acad. Sci., Paris, 230, 788.Google Scholar
Vincke, I. & Lips, M. (1948). Un nouveau plasmodium d'un rongeur sauvage du Congo, Plasmodium berghei n.sp. Ann. Soc. beige Med. trop. 28, 97.Google Scholar
Wedekind, G. (1927). Zytologische Untersuchungen an Barrouxia schneideri. Z. Zellforsch. 5, 505.Google Scholar
Weschenfelder, R. (1938). Die Entwicklung von Actinocephalus parvus Wellmer. Arch. Protistenk. 91, 2.Google Scholar
Wilson, D. B. (1936). Rural hyper-endemic malaria in Tanganyika territory. Trans. R. Soc. Trop. Med. Hyg. 29, 583.Google Scholar
Wolfson, F. (1946). Plasmodium elongatum in the pekin duck. Amer. J. Hyg. 44, 268.Google Scholar
Yarwood, E. A. (1937). The life cycle of Adelina cryptocerci sp. nov., a coccidian parasite of the roach Cryptocercus punctulatus. Parasitology, 29, 370.Google Scholar
Young, M. D., Hardman, N. F., Burgess, R. W., Frohne, W. C. & Sabrosky, C. W. (1948). The infectivity of native malarias in South Carolina to Anopheles quadrimaculatus. Amer. J. Trop. Med. 28, 303.Google Scholar