480 SNAKES OF CEYLON. 



When dry the poison retains its transparency and resembles 

 gum or amber. In the dry state it keeps well and preserves 

 its virulent character, according to Vincent Richards, for at 

 least fifteen y^ars. The same authority shows that, though 

 there has been some difference of opinion among authorities, 

 poison is acid when fresh, and this in spite of the fact that the 

 normal reaction of the cobra's mouth is alkaline. Lamb has 

 confirmed these observations. After the lapse of some hours 

 the venom becomes neutral. Dr. Nicholson says it is slightly 

 bitter to the taste, and causes a feeling of frothy soapiness in 

 the mouth, at the same time stimulating the flow of saliva. 

 The same authority remarks that the dried particles have a 

 pungent action upon the nostrils. Lamb describes the taste 

 as very bitter and astringent. 



(c) Yield : This, of course, varies with the size of the cobra, 

 but even in specimens of similar length other factors affect 

 the yield. Lamb says : " It is an observation of common 

 occurrence in this laboratory (Parel) that a cobra newly 

 caught will yield from 20 to 30 large drops of poison, while 

 after he has been a captive for some time, this quantity will 

 have diminished to from 6 to 10 drops and in time to nil." 

 Dr. Nicholson observed that the yield was more abundant 

 in wet weather. Under the influence of anger, poison is 

 secreted unduly copiously. Doubtless, age, health, and 

 individual vitality also influence the quantity secreted. 



The venom in its fluid state is found to vary a good deal 

 in concentration, a cobra's yield is therefore calculated by the 

 amount of solid residue left after drjdng. Cunningham's 

 average for nine cobras A\-as 254 mgms. Lamb's for fourteen 

 cobras 231, and Roger's for two cobras 249 mgms. Lamb 

 found that by provoking cobras, so as to make them bite 

 viciously, the yield collected in glasses was considerably 

 augmented, as compared mth that collected by simple pres- 

 sure over the glands, and amounted to an average of 373 

 mgms. for three cobras. Cunningham obtained from one 

 cobra the enormous quantity of 725 mgms. The amount 

 of solid, it will be seen, ranges bet'wccn 200 and 726 mgms. in 

 healthy adult cobras. Acton and Knowles have shown that 



