Members of the Aquatic Salamander. 89 



bulbous enlargement of the stump is, however, certainly much less 

 sensible. 



After cicatrization, which is often very tedious, arising* from the 

 exfoliation of the vertebrae, the new growth makes its appearance* 

 preceded by a longitudinal vascular spot. The new growth is a 

 flat triangular projection, the base of which is less than the breadth 

 of the stump. It is perfectly soft and flexible, and of a transpa- 

 rent colour, except at its edges, which are striated with red 

 vessels. 



Although the growth takes place as well from the sides as the 

 apex of the triangle, its increase in breadth does not keep pace 

 with its increase in length. Thus, when it has acquired four lines, 

 the base of the new production is only about five-sixths the breadth 

 of the stump, presenting the form of an isosceles triangle, a mini- 

 ature of the original tail. 



As soon as the new growth of the tail, which takes place much 

 more rapidly than that of the limbs, is about four lines in length, 

 a triangular opacity is observed, projecting into it from the stump. 

 This is the rudiments of the spine, which, together with the forma- 

 tion of the cutis, is the beginning of the process of organization. 



The new growth of the tail bears a much greater proportion to 

 the original size than the new growth of the limbs. The process 

 of organization is much sooner completed, and that of increase 

 requires a much shorter period. In the course of two months from 

 the period of cicatrization, the new tail can with difficulty be dis- 

 tinguished from the original one. 



The processes of reproduction in the larva of the salamander, 

 are exactly the same as in the perfect animal, except that they 

 commence sooner, and are sooner completed. 



Section 2d. Variations of the Process, &c. 



It is a most difficult task, and, I may almost say, a fruitless one, 

 to endeavour to induce any derangement in the process of repro- 

 duction. It is, however, a pleasing one to observe the new means 

 by which nature is ever prepared to adapt herself to every new 

 circumstance and exigency, 



