C82 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



Coelomic Coccidian in an Insect.* — Louis Leger notes that the 

 occurrence of coelomic coccidia in insects is comparatively rare, indeed 

 it has only been recorded twice previously. In the Tenebrionid beetle 

 Olocrates abbreviatus 01., Leger has found, however, a coelomic coccidian, 

 almost if not quite identical with Adelea akidium. 



New Parasite of Brook Trout, f — Mr. G. N. Calkins describes, 

 under the title Lymphosporidium truttee g. et sp. n., a sporozoon parasite 

 which caused an absolutely fatal epidemic among brook trout (Salveli- 

 nus fontinalis) in a hatchery on Long Island. The organism probably 

 enters the digestive tract in the spore stage ; sporozoites penetrate the 

 epithelial lining of the gut and get into the lymph ; there they grow 

 into amoeboid forms which penetrate the muscle bundles ; thence when 

 mature they withdraw, and form spores, possibly after conjugation ; the 

 spores are liberated into the body-cavity or into the lymph and are 

 carried to all parts of the body ; in the muscles of the body-wall they 

 accumulate and block the lymph passages ; the tissues, unable to get 

 sufficient food, die and fall out, leaving characteristic sores and ulcers. 

 The parasite is placed provisionally beside Pfeiffer's Serumsporidium 

 from fresh-water Entomostraca. 



Life-history of Malarial Parasites. J — Dr. M. Liihe gives a com- 

 prehensive historical account of the present state of knowledge on thia 

 subject, and of the steps by which it has been attained. The paper has 

 a very full bibliography, and treats the subject from the scientific point 

 of view as opposed to the practical one, being especially concerned with 

 the relation of the life-cycle in malarial parasites to that of Coccidia. 

 The following table shows clearly the relation of the two phases of the 

 life-history : — 



/Sporozoite = Schizont 



Schizogony 



(often repeated in 



warm-blooded 



animals) 



Merozoite 



Schizont ^ Schizont (schizogony 

 brief duration). 

 Microgametocyte 



Merozoite i 



of 



Macrogamete. Microgamete 

 (Sexual individuals, by 

 means of which the mos- 

 quitos are infected) \ 



Sporogouy 

 (iu the mosquito) 



Copula = "Ookinet" = Oocyst (Sporont) 



Sporohlast 



Sporozoite 

 ( Means of infection of 

 warm-blooded 

 animals) 



* Arch. Zool. Expe'r., viii. (1900), Notes et Revue, pp. i.-iii. 



t Zool. Anzeig,. xxiii. (1900) pp. 513-20 (6 figs.). 



j Centralbl. Bakt. u. Par., xxvii. (1900) pp. 436-60 (9 figs.). 



