Protozoa and Rotifera at Havana, III. 



321 



Fig. 1, Difflugia fra- 



gosa, n. sp. Lateral 



view. 



Fig. 2, Difflugia fra- 



gosa n. sp. View 



showing mouth 



opening. 



Shell composed of fine sand grains, irregular in form, 

 about one and a half times as long as 

 wide, widest at fundus, thence tapering to 

 the mouth where it is slightly constricted ; 

 mouth irregular, slightly notched. The 

 peculiarity of this species is the presence 

 upon the fundus of from one to eight 

 ascending processes or 

 spines, rounded at tip. 

 These originate at about 

 the middle of the shell, 

 giving an irregular out- 

 line to the shell when 



seen from above. Pseudopodia simple, fine, 



and few in number. 



Length .23 mm., width .15 mm. 



It appeared occasionally from August to November of the 



second year in towings, mostly from the river at E, with a 



few from lake substations (G and C). 



Family EUGLYPHID.3E 



Etjglypha Duj. 



Shell uniaxial, formed of round or hexagonal silicious 

 plates in overlapping rows ; mouth opening usually toothed. 

 Pseudopodia not anastomosing. 



19. E. alveolata Duj. 

 Rare, occurring only in a towing from C in May. 



Subclass HELIOZOA. 



(Sun Animalcules). 



Order APHROTHORACA. 



ACTINOPHRYS EHRBG. 



Body soft, spherical, with numerous radiating fine fila- 

 mentous pseudopodia ; endosarc finely granular ; ectosarc 

 vacuolated; division between the two not well marked. 

 Nucleus single, central ; usually a large contractile vacuole 

 in the periphery. 



y 



