44. TRIMORPHODON 887 
than those existing between themselves. Palatine teeth six, 
the anterior three the longest, all longer than the pterygoids. 
The three anterior mandibular teeth longer and more widely 
spaced than the posterior. 
Habits—Nothing is known of the habits of this snake. 
A specimen which I kept alive for a time was very pugna- 
cious and would strike wildly when anyone approached its 
cage. A large female secured at San Jose del Cabo, March 
16, 1892, contained eggs which measured 9x21 mm. One 
of these snakes was found in the thatched roof of a house, 
at San Jose del Cabo, late in the afternoon as it crawled 
over the rafters. 
Family 14. ELAPID 
The snakes of this family are similar in appearance to 
those of the Colubride@, from which, however, they differ 
by their possession of a well developed poison apparatus. 
The poison fangs are situated, on the maxillary bone, near 
the front of the mouth, and are so folded as to form a tube 
for the conduction of the venom into the wound. This 
apparatus they have in common with the closely related sea- 
snakes of the family Hydride. With the latter highly 
specialized family they form the group Proteroglypha. 
The Elapide occur in Africa, Asia, Australia, and both 
Americas. The family includes the most deadly of all 
serpents, such as the cobra and its relatives. Many species 
are said to be viviparous. Only one genus occurs in America. 
