64 THE SECRETIONS: 



the milk of an ass, about a year after foaling, to be com- 

 posed of: 



Analysis 83. 



Water ..... 907-00 

 Butter, with some lactic acid . 12-10 



Casein ..... 16-74 



Sugar, with extractive matter and alkaline salts . 62-31 



The following is the mean of several analyses of asses' milk 

 made by Peligot ; T his numbers approximate pretty closely to 

 mine: 



Water ..... 904-7 



Butter ..... 12-9 



Casein ..... 19-5 



Sugar, extractive matter, and salts . . 62-9 



Chevallier and Henri found in 1000 parts of asses' milk : 



Water .... 916-3 



Solid constituents . . . 83-5 



Butter . . . .1-1 



Casein .... 18-2 



Sugar . . . 60-8 



Salts . . . .3-4 



Asses' milk contains a smaller amount of solid constituents, 

 especially of casein and butter, than cow's milk ; it also differs 

 from it in its great abundance of sugar arid extractive matter, 

 in which peculiarity it resembles woman's milk. 



3. Mare's milk. 



Mare's milk is very rich in solid constituents ; it has a spe- 

 cific gravity of 1034*6 1045'0 ; it contains little butter, but a 

 large amount of sugar. Stipriaan, and Luiscius and Bondt ob- 

 tained from it 0-8 of cream, T62g of casein, and 8*75 of sugar. 

 I obtained a yellow, viscid, saltish, and nearly inodorous fluid 

 from the teats of a mare expected to foal shortly : it coagulated 

 on heating, exhibited a few fat-vesicles and granular corpuscles 

 under the microscope, and acetic acid separated a small quan- 

 tity of casein. It contained 5g of solid constituents, of which 

 only 0*15 was butter. The solid constituents consisted for the 

 most part of albumen, mixed with a little casein, butter, and 

 extractive matter. 



1 Annal. de Chimie et de Physique, Aout 1836, p. 432. 



