280 



C. M. CHILD. 



creeps ; the pharynx is well-developed and sections show that it 

 possesses essentially the same structure as the pharynx in un- 

 injured animals. 



But the difference between the two pieces is most marked as 

 regards change of shape. The piece in alcohol has not elongated 

 at all, in fact it has decreased in length and it may be noted 

 incidentally that the "auricles" on the sides of the head are 

 greatly reduced. The piece in water (Fig. 7) has in the same 



I f 



> t 



4 



length of time elongated to nearly twice its original length, has 

 become much more slender and tapers posteriorly. This piece 

 has moved about during regulation to an even greater extent 

 than the uninjured animal, for short pieces with the old heads are 

 usually more active than whole individuals. 



After ten days the piece in alcohol gradually becomes more 



