6o 



Memoirs of the Indian Museum. 



[Vol. II, 1909.] 



The livers of these animals were of an enormous size; that of the Sting-Ray weighing 

 89I pounds and that of the Saw-Fish i02f pounds. These livers were very rich in oil ; 

 that of the Sting-Ray afforded 71-6 parts of oil, 177 parts of water and 107 parts of 

 hepatic tissue in 100 parts. The hepatic tissue contained over 5 per cent, of nitrogen 

 and would form a valuable manure. All the oils deposited varying amoimts of white 

 fats, chiefly palmitin, at the cold weather temperatures. When freshly expressed the 

 oil has a not unpleasant odour, similar to cod-liver oil, and a colour varying from 

 light yellow to reddish-yellow. 



The following constants were obtained : — 



Specific gravity at 50° C. . . ■( 



Melting point . . . . 22° 



Acid value . . . . ■ 



Saponification value . . . . 194-1 



Iodine value .. ..I24' 

 Reich ert-Meissl 



Fatty acids, per cent. . . ■ ■ 95' 



Melting point of . . ■ ■ 37''. 



Acid value of . . . . 203" 



All these oils contained a cholesterol affording a rose-red or purplish-red colour 

 with sulphuric acid. The slight acidity of these oils is nuich in their favour should 

 they be employed for edible purposes. According to Hosmann the presence of free 

 acids is characteristic of fresh cod-liver oil. Comparatively neutral oils such as these 

 would be much more suitable for medicinal purposes. The large quantity of solid fats 

 would render these oils useful for soap manufacture, while the liquid oil, separated 

 from the palmitin, would be serviceable for leather dressing, lighting and Irubi- 

 cating purposes. 



The livers of various fish have not the same uniform composition as the above. 

 The small skate known as Tiygoii gerrardii in a fresh state possessed a liver 

 weighing only 37 5 grams. This was composed as follows in one hundred parts : — 

 Water . . . . . . . . 56-5 



Oil . . . . . . . . 28-3 



Tissue . . . . . . . . 15-2 



The hepatic tissue contained 11-48 percent, of nitrogen, an amount equal to that 

 found in dry blood. 



