ACANTHOCYSTIS MYEIOSfliSrA. 57 



5. Acanthocystis myriospina Penard. 

 (Text-fig. 191.) 



Acanthocystis myriospina 



Penard Jalirb. Nassau. Ver. Natm-k. XLIII, 1890, p. 23 ; Helio- 

 zoaires, 1904, p. 230, fig. 

 Acanthocystis > sp. 



Leidt Rep. U.S. Geol. Surv. XII, 1879, p. 268, pi. xliii, ff. 8, 11, 13. 

 1 Heterophrys pusilla 



Zachaeias Zool. Anz. XX Y, 1902, p. 665. 



Fig. 191. — Acanthocystis mijriospina. (After Penard.) 



Body small, spherical ; outer envelope composed of 

 one or two layers of minute scales from whicli originate 

 very numerous, delicate radial spines ; ectoplasm, clear 

 or of a blue or bluish-green tint, often containing 

 yellow or dark-coloured food particles; endoplasm 

 placed eccentrically; nucleus small, placed eccentrically; 

 contractile vesicles one or more near the periphery ; 

 pseudopodia numerous, long, attenuate, granuliferous. 



Diameter of body 12-20 yu., usually about 15 [x. 



Spines about the diameter of the body in length. 



