American Species of Rana. 411 
region feebly oblique ; tibio-tarsal arti- 
culation reaching eye; tibia 43 to 5 
times as long as broad, 2} to 2} times 
in length from snout to vent; toes 3 
webbed; male without vocal sacs .... 2. godmani, Gthr. 
Head very large, as long as broad or a little 
broader than long, 22 to 8 times in 
length to vent; loreal region very 
oblique ; tibio-tarsal articulation reach- 
ing anterior border of eye or between 
eye and nostril; tibia 4 to 5 times as 
long as broad, 13 to nearly 2 times in 
length from snout to vent; toes 4 
webbed ; male with external vocal sacs. R. areolata, B. & G. 
Head very large, much broader than long, 
23 to 2% times in length to vent; loreal 
region very oblique; tibio-tarsal articu- 
lation reaching tympanum or eye; tibia 
3 to 83 times as long as broad, 2 to 2} 
times in length from snout to vent; 
toes 4 webbed; male with external 
WOCAL SACS: 7 vals wales: sks, vieronca s Bde coi oie R. capito, Leconte. 
II. Toes ending in very small discs; outer metatarsals separated 
nearly to the base; interorbital space equal to or a little less than 
breadth of upper eyelid ; nasal bones widely separated from each 
other. 
A. Loreal region moderately oblique; toes entirely webbed or two 
phalanges of fourth free. 
1. Tips of fingers swollen; vomerine teeth behind level of 
choane; tympanum 2 to 2 diameter of eye; tibio-tarsal 
articulation reaching tip of snout or beyond; head broader 
than long. - 
No dorso-lateral fold; tympanum distinct ; 
heels not overlapping; tibia 13 to 2 
times in length from snout to vent; no 
outer metatarsal tubercle; male without 
VOC SHCSete ater sts ci otfan dela evo asl leona R., tarahumare, Bley. - 
Dorso-lateral fold, if distinct, very broad and 
flat and restricted to the anterior half of 
the body; tympanum feebly distinct, 
ill-defined ; heels overlapping; tibia 12 
to 14 times in length from snout to vent ; 
an outer metatarsal tubercle; male with 
internal VOeal) SACEE Wa. </c1cfh woes charts. 
A moderately prominent dorso-lateral fold, 
extending to the hip, its distance from 
its fellow, on the back, 3 times in length 
from snout to vent; tympanum very 
distinct; heels overlapping; tibia 1$ 
times in length from snout to vent; no 
outer metatarsal tubercle .,.......... 2, pustulosa, Bley. 
R. boylit, Baird. 
