48 ACANTHOCYSTIS. 



two peripheral layers of vacuoles of more uniform diame- 

 ters. The well-marked distinction between the outer 

 layer of vesicles and the inner mass, distinguishes this 

 from Actinophrys. Diameter, SS// to 400/^ ; rays, 



Hah. Ponds, ditches, lakes, among aquatic plants. 



GENUS YIL ACANTHOCYSTIS. 







SYN. : Trichoda, Schrank ; Actinophrys, Ehr. ; Acanthocysti:,, Carter. 



Animal Actinophrys-like in appearance. Body sphe- 

 rical, soft, composed of finely granular protoplasm 

 mingled with bright-green and colorless corpuscles ; 

 the former absent at times, also containing diffused 

 oil-globules, a central nucleus, vacuoles, and food in 

 balls. Invested with numerous delicate, silicious rays, 

 implanted by minute basal disks and ending in a simple, 

 pointed or furcate extremity ; also giving off numerous 

 delicate, soft rays like Actinophrys further enveloped 

 by a layer of protoplasm, rising in pointed processes on 

 the rays, and pervaded by many exceedingly minute, 

 linear particles ; the enveloping layer sometimes absent. 



Chcetophora. - SYN. : Trichoda ch^iophora, 

 Schrank; Actinophrys viridis, Duj., Perty, Pritchard, Mic. Diet.; 

 Acanthocystis turfacea, Carter, H. and L., Archer, Greeff ; A. viridis, 

 Greeff, Greenacher, Schneider, Leidy ; A. pallida, Greeff. 



Body spherical, bright-green or colorless. Nucleus 

 central, commonly obscured. Silicious, or spiny, rays of 

 two kinds ; one long, strong, and acutely furcate ; the 

 other short, delicate, and widely furcate, sometimes ab- 

 sent. Soft rays simple, granular, as long as, or longer 



