SPOROZOA, GREGARINIDA 539 



U. hardyi Goodrich. In the coelom of Sipunculus nudus; spores 

 about 16m long, process 4-6m long, with eight sporozoites; thin- 

 walled cysts 0.5-2 mm. in diameter; active phagocytosis by host 

 cells of cysts and some trophozoites, producing brownish masses, 

 5 by 2 mm. or more in diameter, which are crowded together in the 

 posterior region of the host. 



Genus Gonospora Schneider. Trophozoites polymorphic, oval, 

 pyriform or vermiform; cysts spherical; spore with a funnel at one 

 end, rounded at the other; in gut, coelom or ova of polychaetes. 



G. minchini Goodrich and Pixell-Goodrich (Figs. 230, g-i; 231, g). 

 In coelom of Arenicola ecaudata; young trophozoites live in host 

 eggs which float in the coelomic fluid; fully grown trophozoites 

 leave eggs in which they grow up to 200m long, and encyst together 

 in pairs; spores without well-developed funnel, 8-10ju long (Good- 

 rich and Goodrich, 1920). 



Genus Lithocystis Giard. Trophozoites large, ovoid or cylindrical; 

 attached for a long period to host tissue; pellicle with hairlike pro- 

 cesses; endoplasm with calcium oxalate cystals; spores ovoid, with 

 a long process at one end ; in coelom of echinids. 



L. brachycercus Goodrich (Fig. 231, a, b). In the coelom of Chiri- 

 dota laevis; fully grown spherical trophozoites up to 200m in diame- 

 ter; spores with a short flattened tail; in Canada (Goodrlih, 1925). 



L. lankesteri G. In the coelom of Sipunculus nudus; trophozoites 

 covered with spinous structures; biassociative; spores 12-14/z by 

 6-8m; the long ribbon-like tail 50-60 m long. 



Genus Pterospora Racovitza and Labbe. Sporadins associative 

 or solitary; free end drawn out into 4 bifurcated processes; cysts 

 spherical or oval; spores with epispore drawn out into 3 lateral 

 processes; in coelom of polychaetes. 



P. maldaneorum R. and L. (Fig. 231, c, d). In coelom of Liocepha- 

 lus liopygue; trophozoites about 140m long; cysts 288m, by 214m; 

 epispore 24/x in diameter; endospore 10-14/* by 3-4/j. 



Genus Ceratospora Leger. Sporadins elongate conical, head to 

 head association; without encystment; spores oval with a small 

 collar at one end and 2 divergent elongate filaments at other. One 

 species. 



C. mirabilis L. (Fig. 231, e, /). Sporadins 500-600m long; spore 

 12m by 8m, filaments 34m long; in general body cavity of Glycera sp. 



Genus Cystobia Mingazzini. Trophozoites, large, irregular; fully 

 grown forms always with 2 nuclei, due to early union of 2 individ- 

 uals; spores oval, membrane drawn out and truncate at one end; 

 in blood vessels and coelom of Holothuria. 



