16 



those of santonine. The crystalline form is only apparent, 

 it is analogous to that of the various pharmaceutical citrates 

 of iron, which though uncrystallizable appear to be crystal- 

 line from the solution having been evaporated on glass plates. 

 A recently captured cobra will yield from six to twenty 

 grains weight of poison, the quantity being greatest in wet 

 weather ; the crystalline residue is from twenty to sixty-six 

 per cent, on the fluid poison. The following extremes and 

 average were obtained in the course of some hundreds of 

 experiments : 



A cobra gave 8 grains of poison, yielding 1 '6 grains residue. 



Do. 7 do. 4-7 do. 



Do. 22 do. 6-6 do. 



Average quantities 6 do. 2 do. 



When being, brushed off the watch-glass on which it was 



dried, the fine particles of dried poison have a pungent 



action on the nostrils ; the taste is slightly bitter and causes 



an increase of saliva having a feel of frothy soapiness. I 



have never found any ill effects from tasting it or from the 



action on the nostrils ; but if any gets into the eye it causes 



a painful inflammation which however soon passes off". 



The properties of this substance will be given more fully 

 in Part III, Chapter IV. 



Before concluding this part of my subject, I may give 

 an account of the structure of the poison fang, prefacing it 

 with the description given by the first odontographer of the 

 age. Professor Owen.* 



" A true idea of the structure of a poison fang will be 

 formed by supposing the crown of a simple tooth, as that of a 

 boa, to be pressed flat and its edges to be then bent towards 

 each other and soldered together so as to form a hollow' 

 cylinder, or rather cone, open at both ends. ***** ipj^g 

 duct which conveys the" poison, though it runs through the 



* Anatomy of Vertebrates, A''ol. I, p, 397. 



