MEXICAN AMPHIBIANS—TAYLOR AND SMITH 533 
rior corner of mouth on upper jaw; and on lower, a part of the larval 
fold which is present in larvae joined to the upper; an indistinct 
groove from eye to angle of the mouth. 
Arms relatively short, the fingers moderately elongate; terminal 
third of metacarpals free on two middle fingers, and somewhat more 
on two outer fingers; order of size 1, 4, 2, 3; tubercles on palm small, 
distinct, the digits somewhat flattened and pointed but the points 
rounded; limbs adpressed, the leg reaches to the base of third finger; 
metatarsals of three middle toes involved in web; the extreme anterior 
part of metatarsals free on two outer toes; order of size of toes 1, 5, 2, 
4—3; toes flattened, pointed; a ridge bordering outer toe continued onto 
the tarsus for a little distance; two tubercles on posterior part of sole, 
elevated, rounded; 12 costal grooves evident high on sides and con- 
tinued across abdomen; a distinct, median dorsal, longitudinal groove 
or depression from occiput to base of tail. Skin of head smooth, with 
traces of pits bordering inner edge of orbit; apparently no trace of the 
lateral-line organs. Outer part of walls of cloaca with a few vertical 
folds; deeper parts with more numerous folds. Dorsal caudal fin very 
low, not rising to a greater elevation than base of tail; ventral caudal 
fin wanting. Glands of the skin are of two visible sorts, a larger 
cream-colored type of gland, and a smaller type of a gray color. Both 
appear somewhat circular and give the skin a characteristic pattern. 
Oolor in alcohol.—Above dull brownish olive, with the cream and 
erayish glands appearing as very minute dots; on venter and half 
way up on sides the color is a dirty cream; arms lighter olive than body.. 
A few dark flecks or spots on head and on back, while the sides of the 
compressed tail are-mottled with olive-black. The lower part of the 
tail lighter olive than upper part; lips somewhat lhghter than snout. 
Measurements in mm.—Snout to vent 107; tail 82; head length 28; 
head width 25; head depth 20; axilla to groin 51; snout to arm 
32; leg 34. 
Larvae.—The largest larva, U.S.N.M. No. 116741, measures 133 
mm. from snout to vent; tail, 108 mm.; head width, 35 mm.; depth 
of head, 25 mm.; length of head (to base of last gill), 44 mm.; snout: 
to median notch of gular fold, 36 mm.; arm, 36 mm.; leg, 38 mm.; 
axilla to groin, 63 mm.; 12 costal grooves. Dorsal fin can be traced 
to a point about 25 mm. behind level of arm insertion. At base of 
tail the dorsal fin is about 5 mm. high; the greatest elevation about 
midway of the tail is 7.6 mm; greatest depth of subcaudal fin 
8.5 mm.; greatest depth of tail, 23 mm.; greatest depth of body, 34 
mm.; the limbs adpressed, the longest toe reaches the wrist; digits 
webbed as in adults, except there is a lateral fold evident along some 
of the digits and the toes are wider, and the fourth toe is longer than 
the third. : 
