XLiv NOTES ET REVUE 



VII 



A iNEW SCHIZOCiREGARINE, MEROGREGARINA AMAROUCII, 



NOV. GEN., NOV. SP., PARASITIC IN THE ALIMEMTARY TRACT 



OF THE COMPOSITE ASCIDIAN, AMAROUCIUM èP. 



(Preliminary Communication) 



by 



Anme Pi)i;teu, li. Se. Lond., 

 Ziiological Rcsearcli Laboratory. University Collège, Loridon 



The term Sclnzof/n'gnriiuie is used fora mosl interesting group of 

 Spurozoan parasites, which includes tlie so-called Avwebospuridia 

 [Ophnjûcijslidae) of Schneidkr (7) logether witii soine otlicr organisais 

 more recenlly described, ail of wliicli, wiiile resembling llie 

 inajority of tlie Gregai-ines iu tlieir structure, liave intercalated a 

 phase of asexual multiplication hy multiple fission or schizogony 

 in their life-history in addition to sporogony. 



The distribution of the Schizogregarines is not a very extensive 

 one. Hitherto gênera hâve ijeen recorded from the alimentary tract 

 and its diverticula of varions Beetles (5), some Annelids (3), 

 Cephalopod Molluscs and Craies. (6). Noue hâve been notitied 

 hitherto from either Prolochovdala or Chordala. The new genus, 

 which Idesignate Merogregarina, is unique in its liabitat, fora species 

 of tlie composite Ascidian, Amnroucitnii, is its host. 



The Ascidian came from Port Jackson, New South Wales, and 

 the material kindly given to me by Prof. J. P. Hill, was fixed eut 

 there, and some of it sectionised some years ago. The systematic 

 position of the host as a species of AiiKironriicm was kindly déter- 

 minée! i)y Professor W. A. Hehdma.n from the material available. 



The material was lixed witli Memming's solution, and portions of 

 it were embedded, sectionised and stained by me in the usual 

 manner. The chief chromatin stains used were iron-haematoxylin, 

 and haematoxylin, while the chief plasma stains used were orange G 

 and eosin. 



The trophozoites of the parasite occur in fair abundance in the 

 gut of the Ascidian, and in inany cases a very heavy infection is 

 produced, the lumen of the gutbeing almost blocked by crowds of 

 the parasites. The schizonts occupy spaces in tlie epithelium of the 

 gut wall. 



