1894.] Vertebrate Fossils. 239 
ters. An atlas vertebra found in connection with the type 
specimen shows a distinct foramen for the inferior branch of 
the first spinal nerve, but presents no other distinctive charac- 
ters. 
AELURODON MEANDRINUS, Sp. n. 
This species is by far the largest of the genus yet described. 
The type consists of the right mandibular ramus, broken off 
at the canine and just back of the sectorial. It indicates an 
animal about the size of the grizzly bear. The jaw was exceed- 
ingly strong and massive in proportion to its length. The 
crowns of premolars two and three are preserved and the roots 
of the sectorial and premolar four. The symphysis is quad- 
rangular in shape and extends backward to below the 
middle of premolar three, its upper border approaches 
very closely the alveolar border. The anterior mental fora- 
men is large and is situated just below the posterior root of 
premolar two. The arrangement of the teeth is especially 
characteristic and has suggested the specific name. The sec- 
ond, third, and fourth premolars are implanted in the the jaw 
in a zig-zag manner. The anterior end of premolar three is 
entirely outside of the posterior root of premolar two. Pre- 
molar four is set quite as much transversely as longitudinally 
in the jaw, its posterior root being as much outside of as 
behind the anterior. The anterior root of the sectorial is 
inside of and overlaps the posterior root of premolar four. 
This arrangement of the teeth is well shown in figs. 1 and 1*. 
The canine was very large as indicated by the alveole which 
is partially preserved. There was a long diastema between it 
and premolar one. The latter tooth was small and fixed by 
one root only. Premolars two and three are small and nearly 
equal in size. Premolar four is much larger than two and 
three. All the premolars are separated by very small diaste- 
mata. The sectorial is exceedingly large, its antero-posterior 
diameter equalling in length the space occupied by premolars 
two, three, and four. In fig. 1 only about half the posterior 
root of the sectorial is shown, thus making the tooth appear 
shorter than it really is. The following are the principal 
measurements of the type. 
