34 , Dr. Gray’s Obfervations on the Oaf of 
pent was venomous. But in many fpecies the teeth are fa 
fmali, that it is impoffible to difcover, merely by looking into 
the mouth, that the animal has any. Yet in that cafe they may 
be very eafily detected, by drawing a pin (or any other hard 
fubftance) with a moderate degree of preffure, along the edge of 
the jaw, from the apex to the angle of the mouth, when they 
will be felt to grate againft the pin, like the teeth of a faw. 
Although the fizeof the venomous fangs is very various, their 
fituation is, I believe, always the fame ; namely, in the anterior 
and exterior part of the upper jaw, which fituation I confideras 
the only one in which venomous fangs are ever found. But as, 
in thofe Serpents which are not venomous, common teeth 
are found in that part of the jaw, it is plain that we can- 
not, by fituation alone, diftinguilh one from the other. They 
may, however, be diftinguifhed with great eafe, and I be- 
lieve alfo with great certainty, by the following {imple ope- 
ration. When it is difcovered that there is fomething like 
teeth in the fore- mentioned part of the upper jaw, let a pin 
be drawn, in the manner already defcribed, from that part of 
the jaw to the angle of the mouth (which operation may, 
for greater certainty, be tried on each fide). If no more teeth 
are felt in that line, it may I believe be certainly concluded^ 
that thofe firft difcovered are what I have diftinguifhed by the 
name of fangs, andconfequently, that the Serpent is a venomous 
one If, on the contrary, the teeth firft difcovered are found 
not to ftand alone, but to be only a part of a complete row, it 
may as certainly be concluded, that the Serpent is not venomous. 
* If a fpechnen fhoufd be met with, in which no teeth, of any kind, can be- 
difcovered in the margin of the upper jaw, the prefumption is, that it is a 
venomous Serpent, which has loft its fangs ; but I have never met with fuch an 
©ne, except the Coluber Ceraftes already mentiohedo 
5 
In 
