FROCKE:DII^aS 



CALIFORNIA ACADEMY 



SCI ENCES. 



ON THE VARIOUS STAGES OF DEVELOPMENT OF 

 SPERMATOBIUM, WITH NOTES ON OTHER PAR- 

 ASITIC SPOROZOA. 



BY GUSTAV EISEN. 



[ With Plate i. ] 



Spermatobium nov. gen. 



The hosts of this parasitic sporozoan are two oligo- 

 chseta, Eclip{d7'ilus frigidus and Phoenicodrilus taste, 

 both found on the Pacific Coast of North America, the 

 former in the Cahfornian Sierra Nevada at high alti- 

 tudes, the latter in the mountains of the Cape Region of 

 Baja California, Mexico, at an altitude of about 4,000 

 feet. In both hosts the Spermatobium is confined to the 

 sperm-sacs, where in the young stages it occupies the in- 

 terior of a sperm cell, but in later stages lives free in the 

 sperm-sac outside the sperm cells. 



Although in the following I have described all the va- 

 rious stages as belonging to one and the same form, it is 

 evident that we here have to deal with two distinct species, 

 of similar structure, but differing very markedly in size 

 of the adult, but principally in the size of the cytospheres. 

 That this difference is not dependent upon the host in 

 which they live is evident from the fact that the Sperm- 



2d See., Vol. V. May 18, 1895. 



