Members of the Aquatic Salamander. 93 



In the anterior half, reproduction goes on rapidly, for in twenty-four 

 days from the beginning of the experiment, four or six of its rings 

 are already reproduced in all about four or five lines in length. 

 As soon as reproduction commences, the round projecting band 

 ceases to be observed. The new production is transparent, of a 

 clear reddish colour, and of the same size and diameter as the 

 rest of the body. The anus is perfectly formed, and the parts of 

 the vessels, nerves, and alimentary canal belonging to the new 

 growth, can be observed, as well as the lateral filaments distri- 

 buted by pairs to each of the new rings. The great ring, it 

 is worthy of remark, entirely disappears during reproduction. 

 The process continues to proceed in the same manner, though 

 with less rapidity, being apparently much influenced by the season 

 of the year. Two hundred and thirteen days from the commence- 

 ment of the experiment the anterior halves have each repro- 

 duced twenty-five or twenty-six rings, the new growth becoming 

 gradually redder, less transparent, and more perfectly orga- 

 nized. Their diameter is every where equal, as well in the new 

 part as the old, so that the new tail continues conical instead of 

 being flattened as in the original. 



The process of reproduction is much slower in the posterior 

 halves. They preserve a healthy and well nourished appearance, 

 their anterior extremity cicatrizes and tapers very much, becoming 

 more pointed, and appearing to assume the form of a bead ; not, 

 however, until fifty-five days from the beginning of the experi- 

 ment can the new growth be distinctly perceived, when only three 

 or four new rings are observed at the anterior extremity, their 

 termination, the seat of the head assuming a pointed conical 

 form, approaching nearer that of the natural head. Two hundred 

 and thirteen days from the beginning of the experiment the pos- 

 terior halves have each reproduced five or six rings, and the head 

 in appearance, (for it does not appear that its real organization 

 was determined by dissection,) only differs from the natural one 

 in being more obtuse and less tapered. 



Thus, from the division of those worms, Professor San Giovani 



