352 THE SECRETIONS: 



The urine of serpents is excreted as a white, pultaceous, 

 earthy mass, which soon stiffens when exposed to the air. It 

 is composed, for the most part, of uric acid in combination 

 with potash, soda, and ammonia, together with a little phosphate 

 of lime. It contains no urea, since, upon digesting it in alco- 

 hol, a yellow extractive matter is taken up, in which no crystals 

 of urea can be detected. 



On the other hand, Berzelius directs our attention to the 

 circumstance that Cap and Henry have obtained urea from that 

 source, after having saturated the uric acid with hydratcd 

 baryta. 



[For an analysis of the urine of the rattle-snake, see Vol. I, 

 p. 53, note.] 



The urine of the bull-frog (rana taurina) consists, according 

 to J. Davy, of a fluid of specific gravity of 1003, which con- 

 tains urea, chloride of sodium, and a little phosphate of lime in 

 solution. The urine of bufofuscus had a specific gravity of 1008 ; 

 it contained a larger proportion of urea than the urine of the 

 frog, together with chloride of sodium and phosphate of lime. 

 In the urine of testudo nigra, which was examined by Magnus 

 and J. Muller, there was no uric acid; on the other hand, there 

 was O'lg of urea, with a brown colouring matter which was 

 soluble in water, spirit, potash, and hydrochloric acid. 



[The urine of a land-tortoise (testudo tubulatd], which had 

 been kept without food for some months, has been recently 

 examined by Marchand. 1 It had a faintly acid reaction, and 

 resembled pus in appearance. He collected 1337 grains, con- 

 sisting of: 



Or in J 000 parts: 



Water . . . 1271 950-64 



Solid constituents . . 66 49-36 



Urea . . .8-5 6-40 



Uric acid . . . 23-0 17-25 

 Ilippuric acid . . none 



Salts and indeterminate organic matter 34-5 25-70 J 



A small quantity of brown liquid fat, with a strong urinous 

 odour, was taken up by ether.] 



1 Erdraann und Marchand's Journ. 1845, iv, 4. 



