TRIPRION. 293 
TRIPRION. 
Pharyngodon, Cope, Proc. Ac. N. Sc. Philad. 1865, p. 193. 
Triprion, Cope, ibid. 1866, p. 127. 
Diaglena, Cope, Bull. U. S. Nat. Mus. no. 32, p. 12 (1887) ; Bouleng. Ann. & Mag. N. H. 1891, 
viii. p. 456. 
Tetraprion, Stejneger, Proc. U. 8. Nat. Mus. xiv. p. 167 (1891). 
Pupil vertical or transversely oval. Tongue entire behind. Vomerine and para- 
sphenoid teeth. Integuments of the head merged into the bones. Fingers and toes 
with disks, the latter webbed. Outer metatarsals united. 
In some of the specimens palatine teeth have been observed, the presence of which 
has led to generic separation (Zetraprion). ‘These teeth are in such a rudimentary 
condition, and consequently so unreliable a character, that this distinction is scarcely 
justified. The appearance of these odontoids goes morphologically hand in hand with, 
and is of no greater taxonomic value than, the ossification of the external integument 
of the head. ‘The three species of Zriprion are evidently so nearly allied that, in this 
instance, I cannot admit even the difference of the shape of the pupil as of generic value. 
1. Triprion petasatus. 
Pharyngodon petasatus, Cope, Proc. Ac. N. Se. Philad. 1865, p. 198. 
Triprion petasatus, Cope, l.c. 1866, p. 127; Journ. Ac. N. Se. Philad. vi. t. 25. figg.7 & 8; Bouleng. 
Batr. Sal. p. 481. | 
Hab. Mexico, Yucatan. 
Canthus rostralis forming a prominent ridge, which terminates in a strong projection 
at the eye, the space between the projections being deeply concave; occipital ridge 
raised ; nostrils separated from each other by a very narrow osseous bridge. Sphenoid 
teeth in a simple series. Tympanum half the area of eye. Fingers one-fourth, toes 
two-thirds webbed. Disks much smaller than tympanum. Upper parts brownish, 
with darker spots ; head with some lighter spots. 
Width of head. . . 1. ww ee ee ee eS mili. 
Distance of occiput from snout . . . . . . . . . 24 ,, 
” vent from snout . . . . . .. . . - ZO ,, 
» ” heel . . 2. ww hehehe COBC*g, 
» 7 metatarsal joint . ... .. 68 4, 
- ” end of fourth toe . . . . . . 84 = ,, 
2. Triprion spatulatus. (Tab. LXXIV. fig. C.) 
Triprion spatulatus, Ginth. Ann. & Mag. N. H. 1882, viii. p. 279. 
Diaglena spatulata, Cope, Bull. U. 8. Nat. Mus. no. 32, p. 12 (1887) ; Bouleng. Ann. & Mag. N. H. 
1891, viii. p. 456. 
Hab. Mexico, Presidio (Forrer). 
BIOL. CENTR.-AMER., Batr., December 1901. #38 
