326 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



similar to those of the chloragogen cells of Tubifex. 

 Rice carried out a series of feeding experiments, and 

 found that neither excess of food, nor starvation, nor a 

 varied diet, had any effect upon these cells. He also 

 pointed out that the granular contents are apparently 

 lifeless, for no stain appreciably affects them, nor are 

 they altered in any way by the addition of strong acids. 

 The lifeless condition of the adult cell suggested to Rice 

 the possibility that these cells have performed their 

 function in the young worm — presumably they would 

 have some connection with the elaboration of food, as they 

 cover the dorsal vessel as well as the intestine — and have 

 become functionless in the adult. This theory is 

 supported by the fact that these cells in a very young 

 worm exactly resemble those of the ordinary peritoneum. 

 In the larger worms a gradual development into typical 

 chloragogen cells can be traced. The cells increase in 

 length, the characteristic granules appear, and they 

 become less and less responsive to stains, with the 

 exception of the nucleus which stains throughout. 

 Earlier observers believed these cells to be secretory in 

 function, but, judging from their lifeless condition in 

 the adult, their function, if any, would surely be one of 

 excretion rather than secretion. 



CIRCULATORY SYSTEM. 



The circulatory system, as in all other Oligochaeta, 

 is a closed one, having no communication with the coelom. 

 It consists of a series of main vessels having a longitudinal 

 direction, and united with one another by lateral vessels 

 in each segment. The blood vessels are well-developed 

 tubular structures, and their walls are very delicate. In 

 none of the vessels does there seem to be an epithelial 



