a 
THE BIS COBRA Td 
tion of future bis cobras. The belief in poisonous lizards is by no 
y 
means confined to India. It may safely be said that there is no known 
species of lizard in the old world which is provided with glands 
for secreting venom, or fangs through which to eject it. Nor are 
there any lizards in India whose dentition is in any way suspicious. 
It must, however, be admitted that there is rather strong evidence, 
if not actual proof, as to the existence of a venomous lizard in 
Mexico. This is the Mexican Heloderm (Heloderma horridum, Wieg- 
mann), a species of the monitor family. Mr. Tegetmeier has writ- 
ten an interesting account of this reptile in the Field of August 19th, 
1882. The Heloderm was first described by Dr.. W iegmann in 
1829. It had long been held to be venomous by the inhabitants of 
g J 
the tract in which it is found, that is the hot zone of Mexico Dr. 
Wiegmann called attention to its peculiar dentition, which seemed 
to confirm in great measure the popular belief in its poisonous 
nature. For although there were no signs of poison glands, as in 
the case of venomous snakes, it was found to have recurved grooved 
teeth, through which its saliva, whether poisonous or not, could be 
introduced into the puncture made by its bite. Dr, Wiegmann 
himself does not appear to have believed that the Heloderm was 
really a venomous species, and he made no experiments to test the 
matter. Many years later,a French naturalist, Sumichrast, took up 
the subject again, and wrote a more detailed account of the Helo- 
derm in the Comptes Rendus of 1875. THe also procured and sent 
preserved specimens to Paris. According to Sumichrast the animal 
has a strong nauscous smell, and when irritated seerctes a large 
quantity of glucy saliva. ‘In order to test its supposed poisonous 
property”—I am quoting from Mr. Tegetmcier—** he (Sumichrast) 
‘aused a young one to bite a pullet under the wine. In a few 
minutes the adjacent -parts became violet in colour, convulsions en- 
sued, from which the bird partially recovered, but it died at the 
expiration of twelve hours. A large cat was also caused to be bitten 
in the foot by the same Heloderm; it was not killed, but the limb 
became swollen, and the cat continued mewing for several hours, as 
if in extreme pain.’ Mr. Tegetmeier further writes that the dead 
specimens sent to Wurope were carefully examined as to the charac. 
ter of the teeth. Sections wero made, which demonstrated the 
existence of a canal in each tooth, totally distinct from and anterior 
to tho pulp cavity; but the soft parts were not examined with 
sufficient care to determine the existence or otherwise of any 
1 
