102 Observations on the Natural llistory 
afterwards in a right line, till they reach the anterior point of 
the kidneySj where they make many twistings, and pursue a ser- 
pentine course, till they arrive at the lower half of those organs. 
In the females of these reptiles, on the contrary, the ureters are 
less convoluted, and do not commence at any distance from the 
kidneys; whence, it is probable, that from this difference of 
form, the ureters of the male may exercise some other office be- 
sides that of conveying the urine. In Fig. 3. Plate VI., the 
kidney of a female may be seen. 
But though the kidneys and ureters in the proteus and 
salamander bear so near a resemblance, the form of the uri- 
nary bladder in the two animals is quite different. In the 
salamander, this organ is short, and its fundus bifid. In 
the proteus it is long, and has a simple fundus; so that it 
resembles more an appendix coeci of the intestine, than an 
urinary bladder. It is annexed to the intestine in a point 
diametrically opposite to that into which the two ureters are in- 
serted ; in other words, it is inserted into the wall of the intes- 
tine that looks downward, while the ureters terminate in the wall 
that regards the spine. In the proteus, therefore, as in other 
reptiles of the same family (Batraciens,) the ureters do not ter- 
minate in the bladder, but discharge themselves directly into the 
intestine, at a point opposed to the bladder. This fact has led 
many, and among others Townson and Schreibers, to doubt if 
the organ named the urinary-bladder, be, in frogs and salaman- 
ders, a real receptacle for the secretion of the kidneys, or destin- 
ed to some other office. Townson, supposing the urine poured 
into the intestine by the ureters to be at once discharged with 
the feces, suggests the idea, that the bladder above mentioned 
may be regarded rather as a reservoir of water absorbed from 
without, and destined to some particular use in the animal eco- 
nomy. His words are, 66 Cum nunquam bibant base animalia, 
opus tamen sit iis tan topere aqua, probabile mihi videtur, aquam 
cute absorptam, aut ejus partem induci in vesicam, tanquam 
in vas quod earn servet; atque inde distribiii, prout economva 
animalis requirat, eodem fere modo, quo fluidum receptum 
in ventriculum aliorum animal him inde distribuitur That 
the skin of frogs absorbs water, seems demonstrated by the re- 
See Townson- Observationes Physiologies cte Amphibiis, &c. 
