36 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [BuU. 



At the base of the flagellum two contractile vacuoles. Nu- 

 cleus posterior; usually with many starch grains in the 

 posterior part of the body. Multiplication by fission (in- 

 side of the shell) into four or eight parts which then be- 

 come free. 

 P. uvella Ehrbg., Fig. loi. 

 Hexamitus Duj. 



Body ellipsoidal, somewhat flexible. The anterior end 

 rounded or acute, with two flagella. The posterior end 

 either truncated or prolonged into two thread-like caudal 

 processes. The animals appear very variable in form. 

 Nucleus near the flagella and contractile vacuole posterior. 

 H. inflatus Duj., Fig. 97. Fig. 98 is probably a variety of 



the same, and also Fig. 113. 

 H. spiralis (?) Stokes, Fig. 105. 

 Trichomastix Btitsch. 



Pear-shaped to elongated, rounded in front, acute be- 

 hind. In front four flagella, of which three are usually 

 carried close together, appearing as one, while the other 

 is commonly carried behind as a trailing flagellum. The 

 anterior flagella may be separated as shown in the figure. 

 The animal figured in Fig. 118 does not appear to re- 

 semble any described genus, but I place it here as being 

 more like Trichomastix than any other genus. Tricho- 

 mastix is described as parasitic. Our animal was found 

 in great numbers in a watering trough. 

 Ochromonas Wys. 



Oval to pear-shaped, amoeboid. One long and one 

 secondary flagellum. Mouth at base of flagellum. One 

 or two yellowish chromatophores and an eye-spot. An- 

 terior contractile vacuole and central nucleus. Free swim- 

 ming or attached. 

 Och. sp. (?), Fig. 43. 

 Cryptomonas Ehrbg. 



Identical in anatomy with Chilomonas, but with two 

 brown or green chromatophores. 

 Crypt, ovata ( ?) Ehrbg., Fig. 99, a. b, c. Three varieties, 

 possibly different species. 



