GREGARINA. 



og- 



34. Gregarina aciculata, sp. nov. (Fig. 36.) 



fGregarine parasite, "species B," Cornwall, 1915, pp. 130-1, pi. x,. 

 fig. 31 ; pi. xi, figs. 37, 38. 



Young trophozoite intracellular in a swollen cell of the 

 stomach. Full-grown trophozoite cordate, with a long acicular 

 epimerite, penetrating between the epithelial cells right down 

 to the basement membrane. Free individuals often assume 

 peculiar shapes during syzygy. Sporonts coalesce, acquire 

 a common capsule, and become small, white, shining gameto- 

 cysts, only just visible with a lens. These cysts are passed out 



Fig. 36. — Gregarina aciculata, sp. nov. A, adult trophozoite ; B, gameto- 

 cyst with spores coming out in a long chain. (After Corn- 

 wall.) 



with the faeces, and often several are found in the same mass. 

 Gametocysts possess a thick, smooth wall and a central sporal 

 mass. In the course of seven days or so protrusions from the' 

 inside develop into curved or angular tubes about as long as the- 

 diameter of the cyst. Sporocysts are then thrust out through 

 these tubes in long strings. Sporocysts very small, about 4ju, 

 by 2)u,, symmetrically curved, and joined end to end. Dehis- 

 cence is along one border. 



h2 



