198 
On the Teeth and Poison 
can here trace the changes as they take place from the almost 
invisible rudiment up to the perfect fang. 
The first appearance of a tooth which the microscope can 
detect, is a small osseous cone—the point of the future fang. 
On the side of this a small indentation is soon observed, 
which, as development proceeds, gradually assumes the form 
of a deep cavity, presenting the appearance as if a portion 
had been scooped out from the side and periphery of the 
base of the cone. By and by, the lower margins or lips of 
the cavity thus formed, instead of remaining apart, commence 
gradually to arch across it, and finally approximate and meet 
in the mesial line, forming thus a complete bony ring. This, 
of course, is the beginning of the canal, and the so-called 
cavity is now the distal opening. The formation of the 
canal afterwards proceeds equally with that of the tooth 
itself, till the process of growth is nearly completed. Just, 
however, before the formation of the base commences, the 
canal ceases, and the “ lips” which we have already seen 
arching across to complete the tube, and which have hitherto 
remained in close and osseous union, now again separate 
slightly in order to form the proximal orifice. The large, 
articulating base now alone remains to be added, and when 
this is formed, the development of the fang is complete. 
The canal is of considerable size, allowing free transmis¬ 
sion to a moderately sized hair, and its distal opening is of a 
more elongated form than the proximal. Every part is per¬ 
fected during the process of formation, and no alterations or 
changes are afterwards required- Hence it is, on examining 
the point of the fang when not more perhaps than the six¬ 
teenth of an inch in length, the distal opening (which of 
course is the only one then formed) is found to be as fully 
and perfectly developed, as in the fixed fang. Between the 
orifices, which it will be recollected are on the anterior and 
convex surface of the tooth, a faintly marked longitudinal 
groove may always be traced, shewing the point oi 
