no The Ottawa Naturalist. [July 



while the lophophore is thus expanded. Another set of muscles 

 assist in closing the opening of the ccencecium, when the body 

 is withdrawn ; or are attached to the stomach, which assist that 

 organ in its functions. 



Pluniatella repens feeds on infusoria and small algae which 

 are drawn into the mouth by the currents created by the cilia 

 attached to the tentacles. These cilia have an upward move- 

 ment on one side of the tentacles and a downward one on the 

 other. 



Reproduction occurs in two modes : («) by budding, (/;) by 

 statoblasts or winter eggs. Reproduction by budding merely 

 increases the number of individuals in each colony, whilst re- 

 production by statoblasts assists in forming new colonies. 



Statoblasts are flattened discs, round or oval, formed within 

 the body, and escape after the death of the polypide when the 

 whole colony disintegrates. Statoblasts are dark brown in 

 colour and have an outer ring called the Annulus, formed of 

 hexagonal cells. Others have barbed hooks along the margin. 

 Statoblasts are excellent criteria for distinguishing one genus 

 from another, or the different species of each genus. 



Locality and habitat. Abundant on logs, sticks, stones in 

 Patterson's Creek and in pits at Odell's Brick Works where the 

 largest colony observed was found on a piece of board five feet 

 long and ten inches wide entirely covering the under surface 

 with innumerable colonies of this species. August 1898. 



Fredericella regina, Leidy. 



This species is found growing with the preceding, which, 

 it resembles somewhat in appearance. It is dendritic in form, 

 of a light brown color, and usually attached by the trunk, the 

 branches being mostly free. It covers a smaller area than 

 Plumatellaand is readily distinguished from itbyits characteristic 

 circular or oval lophophore, that of the former being horse-shoe- 

 shaped. The tentacles are few in number, generally nineteen, 

 and arranged on the crest in a single row. Contrary to the 

 statement made by Hyatt and other workers on Polyzoa, Fred- 

 ericella regina found at Ottawa was found in nearly every 



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