116 THE DESEADO FORMATION OF PATAGONIA 
sider females. Practically all of the other species are based 
on mandibular symphyses varying in details from the 
above, but in no case sufficiently for me to see a specific 
variation. 
The general features have been discussed under the 
generic description. Incisor 1 has a long crown and a 
long root, and is greatly crowded by the tushes. Incisor 3 
and pm. I have the same crowded appearance. In giving 
the measurements I have used a skull which is typically 
L. gaudryt, a male, and parallel to it have put another skull, 
which is typically L. oxyrhynca, the female. By compar- 
ing the two sets of figures, the shortening, of which Ame- 
ghino speaks, will be seen to be all in the region of the 
tushes. 
SPECIMEN 3290 SPECIMEN 3291X 
MALE FEMALE 
Upper dentition, length from inc. 1 to m. 3 227 mm. 
Upper dentition, length from pm. 1 to m. 3 180 mm. 
Incisor 1, length I2 mm. 
Incisor 2, length 25 mm. 
Incisor 3, length Il mm. 
Canine, length I2 mm. 
Premolar 1, length 12 mm. 
Premolar, 1 width 18 mm. 
Premolar 2, length 18 mm. 
Premolar 2, width 28 mm. 
Premolar 3, length 20 mm. 
Premolar 3, width 34 mm. 
Premolar, 4, length 22 mm. 20 mm. 
Premolar 4, width 38 mm. 34 mm. 
Molar 1, length 28 mm. 24 mm. 
Molar 1, width 4o mm. 38 mm. 
Molar 2, length 36 mm. 33 mm, 
Molar 2, width 48 mm. 45 mm. 
Molar 3, length 46 mm. 46 mm. 
Molar 3, width 48 mm. 47 mm. 
Lower dentition, height of mandible underm.1 66 mm. 56 mm. 
Incisor 1, length 8 mm. 8 mm, 
Incisor 2, length 10 mm. 10 mm. 
Incisor 3, length 23 mm. 13 mm. 
Canine, length : 8 mm. g mm, 
Premolar 1, length 13 mm. 8 mm 
