250 DESCRIPTION OF [Polygastrica, 



horse-shoe shaped spot, and forms an essential character 

 of the genus. Longitudinal self-division has been ob- 

 served only in G. cinctum. 



381. Glenodinium cinctum. The yellow Glenodinium. 

 — Lorica oval, or nearly spherical, and smooth ; eye large, 

 semi-lunar, and transverse. Found in fresh water, amongst 

 oscillatoria. Size 1-5 70th. 



382. Glenodinium tahulatum. The tabulated Glenodi- 

 nium is oval, of a yellowish green colour; the lorica 

 is granulated and reticulated with elevated lines, but 

 not spinous ; truncated and denticulated posteriorly, 

 and bidentate anteriorly ; eye oblong. Size l-570th to 

 l-430th. 



383. Glenodinium apiculatum. The spinous Glenodi- 

 nium is oval, of a yellowish green colour; the lorica is 

 smooth, but tabulated at the margin with hispid furrows, 

 as shewn in figures 224, 225, and 226. The eye is ob- 

 long, and extremities obtuse. Found amongst conferva, 

 where chara grows. Size l-570th to l-430th. 



