FRESH-WATER POLYZOA. 



253 



series, and are preserved during the cold of winter until 

 under the favorable condition of spring, they put forth 

 buds and branches, which, by separation and settle- 

 ment elsewhere, become the foundation of new col- 

 onies." 



I have known the statoblasts of Pectinatella to be 

 formed in so great profusion in the autumn, that the 

 surface of a pond perhaps half an acre in extent, was 

 as densely covered with them as the surface of the lit- 

 tle pools along the railroad is sometimes covered with 

 cinder-scales. It is these statoblasts which are so 

 often seen as dark-brown little bodies thickly stud- 

 ding the surface of the half-dead masses of Pectinatella 

 jelly in September or later, and floating on the water, 

 or entangled among Alg£e or other aquatic plants, 

 whence they are not rarely collected by the microsco- 

 pist and come to the microscope-stage to make the 

 observer wonder. 



Although small, the largest n»easuring perhaps Jjj- 

 inch in diameter, their richi, dark-brown color makes 

 them easily visible even to the naked eye, especially 

 when in any abundance. 



ft h 



Fig. 173. — Statoblast Fig. 174.— Statoblast 

 of jredericella. of Plumatella. A, 



anriulus. 



Fig-. 175. — Two forms of Stato- 

 blast of Lophopus. A, 

 annulus. 



They are all oval or subcircular in outline, and 

 much flattened, while some are bordered by one or two 



