45] STUDIES ON GREGARINES KAMM 45 



GANYMEDES Huxley 1910:55 



A possible fixation organ at interior end, consisting of a motile stalked 

 sphere. Cup at posterior end which fits into ball of a satellite. No sep- 

 tum, no true epimerite. Typical gregarinoid encystment, cysts spherical. 

 Alimentary tract of Crustacea. 



Huxley offers the hypothesis that this gregarine lies between the 

 polycystids and the monocystids and creates for it a new family, Gany- 

 medidae. Since his studies were made only upon fixed material and all 

 characters of this very unusual parasite are unknown, I think the rank of 

 a new family is hardly justifiable and prefer to consider it among the 

 Genera of Uncertain Position. 



GANYMEDES ANASPIDIS Huxley Type Species 



[Figure 89] 



1910 Ganymedes anaspidis Huxley 1910: 155 



1913 Ganymedes anaspidis Ellis 1913: 264 



Characters of the genus. Sporonts in pairs, elongate cylindrical, 

 maximum length 200ju, width 120/i. Average size 250ju to 300/* by 17 n 

 to 20ju. Nucleus large, ellipsoidal, one large karyosome. Cysts spherical, 

 IQQfjL in diameter. 



Anterior end of protomerite a "distinct stalked sphere," 8 to 10/z across. 

 Protoplasm of anterior end highly specialized, posterior end a socket into 

 which fits the "ball" of another individual, during the associative period. 



Intestine and pyloric caeca of Anaspides tasmaniae (Thompson). 



Taken on the Island of Tasmania. 



Intestine and ? coelom of Gammarus pulex. 



von Siebold described Didymophyes longissima from the same host, 

 considering it a second form of the same species. In the same paper, 



