90 W. M. Carpenter on the Muscles in the Glass Snake. 
These animals have the’ external form of serpents, but re- 
semble the lizard family in general structure. ‘They constitute 
the transition type between the Lacertian and Ophidian reptiles. 
The genus Ophisaurus owes its name to this circumstance, ( Og, 
serpent, s«vgos, lizard.) It includes several species inhabiting the 
southern parts of the United States, principally the pine forest and 
prairie regions. They have about 150 vertebral bones, about one 
third of which belong to the body and two thirds to the tail; 
the body is consequently very short when compared with the tail. 
All of the species receive indiscriminately the name of Glass 
snake from the extreme fragility of their tails. A very slight stroke 
with a small rod, or trifling violence inflicted by any other means, 
will cause the separation of a part of the tail from the body, and the 
tail will sometimes break into a number of pieces. The body 
and attached parts continue to live, and in process of time the 
lost portions are replaced by a new growth. 
If we examine the parts separated, in an animal which has 
been thus broken, or what is preferable, drawn asunder, several 
little conical and pomted fleshy processes, may be observed, sur- 
rounding the vertebral bones, and projecting several lines beyond 
their articulating surfaces, and which must have been drawn out 
of cavities in the muscles, that correspond in position on the adja- 
cent vertebral bones. 
iad. 7: 
In figure 1, I have endeavored to represent an enlarged view 
of this appearance. Lines drawn across the figure from the 
points a to a’, b to b’, ¢ to c’, and d to d’, may represent the. posi 
tion of the separated articulating surfaces of the adjacent verte- 
bre, which, when in their natural positions, would of course be 
m contact ; and it is easy to see that when these are in contact, 
the conical muscles, which project so much beyond them, must 
fit into corresponding cavities of their own size, in the muscles 
corresponding in position with them on the next bones. If one 
of the vertebrae is examined separately from the rest while su 
rounded by its muscles, it will be seen that each vertebral bone 
