1871] 83 
[Cope. 
over the origin of the nutritious foramen on each side, into a shelf: gen- 
eral form longitudinal oval. The superior direction of the median radius 
of the cotylus for the last phalange, shows that the claws were always 
flexed to some degree. : 
Fragments of many long bones, including many condyles, accompanied 
the above, but in the lack of certainty as to their proper reference, are 
not described. 
This species is dedicated to Charles M. Wheatley, of Phonixville, to 
whom Natural Science in the United States is under many obligations. 
The expense and much labor requisite for the proper recovery and elucida- 
tion of the remains contained in the cave are entirely due to his liberality 
and exertions. Similar devotion to Science has preserved to us the finest 
series of fossils of the triassic period of the Northern States in exist- 
ence, and the finest collection of fresh water shells in America. 
MzGALONYX Disstmitis, Leidy. 
Proc. Acad. Nat. Sci. Phila., 1852, 117. Sloth tribe N.,A.,. 45,.Pl. xiva 
figs. 4—8, xvi., 8 and 15. 
Probably represented by three canine molars, which belong to at least 
two individuals. They have been described under head of the pre- 
ceding species (see 1 ac). The canine molars are the only ones which 
can be compared with Leidy’s figures and descriptions, with which they 
agree closely. 
Measurements of teeth. 
M. 
Long diam. canine molar, larger individual oflac.............. 0.0386 
Short “ye Me Bs as cee Ge is .0158 
MOM. se sh smaller Ole ee era ee 032 
BuO °° re ee eer ers .014 
Length shaft - as Ae eae csr oe 079 
This species is evidently about the size of the M. wheatleyi and M. 
jefferson. 
MEGALONYX SPHENODON, Cope. 
Yhis species is the smallest of the genus yet known from North Amer- 
ica. It is indicated certainly by the canine-molars of opposite sides of 
one individual only. 
These teeth are flat and a little curved. <A principal peculiarity con- 
sists in the regular increase in their diameter, from the apex to the base, 
in both the longitudinal and the transverse directions. The long diame- 
ter of the triturating surface is four-fifths that of the base where broken 
off. The dentinallayer is thick externally ; it contracts after turning, 
and the layer of the inner aspect is uniformally thin, but less so than in 
M. dissimilis. The inner bulge is well marked, and is a little nearer the 
anterior margin than the posterior; the latter is the thicker. The tritur- 
ating surface is slightly oblique in the long direction, as in the two species 
\ 
