and Structure of the Aquatic Salamander. 123 
f, the stomach ; g , the intestinal canal ; h , the lung of the left 
side. 
28 th May . — The same salamander, of the natural size, seen 
from above. It is about this period that the hind paws begin 
to appear ; the fore paws have acquired their perfect develop- 
ment, and are long in proportion to the trunk, as is more dis- 
tinctly seen in the microscopic representation of it, fig. a. 
Without entering into minute details of the changes which have 
occurred in the ten days elapsed, and which an inspection of the 
figures will sufficiently illustrate, the author proceeds to ob- 
serve, 1*£, That, at this epoch, we begin to see, on the two sides 
of the trunk, with the aid of the microscope, two lines of small 
salient points or excrescences, which extend from the axils to 
the extremity of the abdomen. 2 dly, That the walls of the ab- 
domen have not colour in themselves, but that they present the 
colours of the insects on which the animal has fed. Sdly, That 
the changes of colour from yellow to green, which occur during 
the growth of the tadpole, are purely accidental, and begin im- 
mediately after its escape from the egg. 4 thly, That the toes, 
which are most interior, first push forth, as well in the hind as 
in the fore feet. Stilly, That the pierre amylacee of the organ 
of hearing, is, at this period, formed, and is visible through the 
cranium and skin that cover it. Stilly, That at this epoch, and 
even sooner, the animal begins to expel air from his mouth. 
12 th June . — The same salamander seen from above, of its 
natural size, and also in profile (a), when magnified. The hind 
paws have almost attained their development, but as yet the 
fifth toe is wanting ; the lungs extend only about half way down 
the trunk, and are visible through the walls of the abdomen ; 
the gills, which are longest, have nearly twenty leaflets ; they 
had only thirteen or fourteen ten days before. 
18 th July . — The same salamander, now arrived at the matu- 
rity of its tadpole or larva state. It is represented at the mo- 
ment in which it watches a little slug, to ascertain its living 
state ; for neither salamanders nor frogs ever fall on their prey, 
till after having seen it give signs of life. 
On this day, says the author, the gills of this tadpole ap- 
peared a little less long than on the day before ; whence he 
suspected it was about ready to pass to the state of the per- 
