304 [Avaust, 
other, as in the wolf, but more nearly equal in size and forming together more 
of a triangle. 
Measurements. 
Length of cranium from occipital condyle to the narrowest 
portion of the former, which is just in advance of the 
bifurcation of the sagittal crest 3in. 5 lines. 
Breadth of cranium at most prominent part deh ibe: 
OG ce where narrowest OAs 
Depth of lower jaw below last molar iS 
Antero- posterior diameter of last lower molar 2p 
a é penultimate lower molar AN Nsé 
6< “< ante-penultimate *¢ SG 
Transverse diameter of Jast upper molar Dace 
36 <é penultimate “ , 5: 66 
ce sé ante-penultimate molar Ue 8 
1. Leptomeryx Evawnsi, Leidy.—-This is established upon a craninm which 
has lost the nose, and is broken at the parietal region. ‘The specimen contains 
upon one side all the molars, six in number, and upon the other side the posterior 
four molars; and it is accompanied by a portion of the lower jaw containing the 
true molars and the last premolar. . 
The genus is closely allied to the existing Moschws,and the species was about 
the size of the M. Javanicus. The six superior molars form a_ closed 
row, in advance of which a hiatus exists. The true molars are composed 
of four lobes resembling those of recent musks, but they possess a peculiar 
generic distinction, which is a tubercle rising out of the base antero-inter- 
nally of the postero-internal lobe, about one-third the size of the lobes themselves, 
and appearing as if it wasa rudimentary fifth lobe. The third premolar consists 
of two lobes as in the musks, and the anterior two premolars in section are tri- 
lateral and consist of a broad external and a narrow internal lobe. 
The lower true molars are like those of the musks, but in the last of the series 
the ordinary fifth lobe of ruminants is. notched so that there are actually six lobes 
to the tooth. The last premolar is worn in the specimen into a surface, resem- 
bling in some degree the figure 3 in shape. In comparison with Moschus Javanicus. 
the forehead of Leptomeryz Evansi has about the same inclination forward and 
is almost as broad; but the sagittal crest is longer and the temporal fossx are 
more horizontal and more capacious; the orbits are smaller and more directed 
upward; the zygoma is deeper; the post orbital arch is more vertical, and, if 
the specimen is a correct representative of the species, it isopen for about aline ; 
the glenoid articulation is more deeply concave, and it possesses a strong post 
glenoid tubercle; the auditory bulle are much smaller; and finally the inion is 
broader. 
Measurements. 
Length from occipital condyles to first molar 2in. 10 lines. 
Breadth at zygomata QwisS 
Length of upper molar series NaS) Aw cc 
ce series of lower true molars 11 
‘Fransverse diameter of orbit 10“ 
Vertical %G sé lek 
The species I have named in honor of its discoverer, Dr. John Evans. 
Of turtles the collection contains numerous carapaces, which present such a 
gradation of form, size and growth to the five species described in the ‘* Ancient 
Fauna of Nebraska,”’ that I feel doubtful whether there is more than one species 
among them, for all appear to me to be only different ages of Testudo lata, the 
only one which was represented as full grown, as indicated by the sutural con- 
nexion of the costal with the marginal plates. 
(The specimens upon which were established the new species and genera in this 
communication were exhibited by Dr. Leidy tothe members.) 
ELECTIONS. 
Dr. G. Emerson, of Philadelphia, was elected a Member, and the Rey. 
Thomas G. Porter, of Lancaster, Pa., was elected a Correspondent. 
