44 



BRITISH FRESHWATER HBLIOZOA. 



solitary habits, also in the appearance of the plasma 

 with its numerous coloured inclusions, but the outer 

 investment formed of ovoid instead of spherical 

 globules and its more exactly circular outline 

 differentiate it clearly. 



Fia. 187. — Pomphohjxophrys ovuligera. X 900. (After Penard.) 



P. exigua Hertwig & Lesser is distinguished from 

 both this and the preceding species by the veiy minute 

 size of the globules forming its outer covering. 



Genus 7. LITHOCOLLA F. B. Schulze. 



Lithocolla F. E. Schulze Arch. mikr. Anat. X, 1874, p. 389. 



Plasma enclosed in a spherical outer envelope'com- 

 posed of heterogeneous silicious elements, usually 



