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POPULAR SCIENCE REVIEW. 
robust body. They are not, however, often fatal to man, and 
in this respect they offer a striking contrast to the American 
Crotalidse. While statistics prove that death in some instances 
follows the bite of the larger Trimerisuri, it is still easier to 
show that its more common effect is but a train of unpleasant 
symptoms, of varying duration, ending in recovery. The 
general health and vigour of tlie patient usually enable him to 
resist the influence of the venom, where a more weakly subject 
would probably succumb. There is still less evidence of tlie 
homicidal powers of the other Indian Crotalidse. Of these the 
most interesting is the genus Halys, represented by two species 
in British India. Halys is remarkable for the long spinous 
scale in which its tail terminates — a rudiment of the “ rattle ” 
which some of its formidable American relatives possess. 
Of the two Indian Viperidse one is the ‘ Tic-polonga,’ or 
Eussell’s viper, a most fatal snake. The other is the little 
Echis carinata, a species, however, which can no longer be 
separated from the Echis arenicola of Egypt. This prettily 
marked brownish snake may reach a length of twenty-three 
inches ; usually it is much smaller. Evidence as to its lethal 
powers is wanting. Dr. Griinther, writing in 1864, was not 
able to prove that its bite is ever fatal to man. Dr. Fayrer 
holds a more positive opinion, judging from the fact that an 
Echis in his possession “ killed a fowl in four minutes, another 
in two minutes, and a dog in about four hours.” He describes 
it as “ very fierce and aggressive — it is always on the defensive — 
ready to attack ; it throws itself into a double coil, the folds of 
which are in perpetual motion, and as they rub against each 
other, they make a loud rustling sound, very like hissing. This 
sound is produced by the three or four outer rows of carinated 
scales, which are very prominent and point downwards at a 
different angle to the rest ; their friction against each other 
causes the sound.” He adds that “ its eye has a peculiarly 
vicious appearance.” 
The Elapidse having the sides of the neck dilatable to form 
a hood constitute the sub-family of JSTajidae. This group con- 
tains two genera, of which both are Indian. Naja itself is 
represented by the famous Cobra (N. tripudians), a near relative 
of the Egyptian Haje (N. haje). Another hooded snake, Ophio- 
phagus elaps, the only species of its genus, ranges from the 
Indian peninsula to New Gruinea. 
Of Indian Elapidas without a hood the most noteworthy are 
the two species of Bungarus. B. cosruleus is the dreaded 
“ Krait.” The much larger B. fasciatus, a species marked by 
broad alternate transverse bands of black and yellow, is by no 
means so fatal in its effects. For the rest, excepting one or 
two doubtful snakes, the Elapidse are represented on the Indian 
