464 The Lemuroidea and the Insectivora of the [May, 
best known is the T. rostratum from the Bridger formation of 
Wyoming. 
The following points may be gained by comparison with the 
skeleton of Lemur collaris (catalogue Verreaux). There is con- 
siderable resemblance in the details of structure of the molars 
from the third to the sixth, inclusive. Of course the anterior 
teeth differ widely in the two, and the last true molar of the 
Lemur has no heel. The principal difference in the humeri is 
seen in the superior size of the epicondyles of the T. rostratum, 
and the rather more robust character of the shaft. The proximal 
half of the ulna is deeper, and the olecranon is not so wide in 7. 
rostratum. The proximal part of the radius is very similar 
in the two species, but the distal extremity is in the 7. res- 
tratum less transversely extended, and thicker anteroposte- 
riorly. There is also much similarity in the ilia. The crest is 
more extensive in T. rostratum, and the inferior border is thinner 
at its proximal part. Towards the acetabulum the increase in 
width of this border is similar, and the anterior inferior spine is 
as prominent. The resemblance between the femora amounts to 
identity of character; that of the T. rostratum is more robust. 
The Mixodectide include four and perhaps five genera. In 
Fic. 8.—Necrolemur antiquus Filh., skull natural size, from Phosphorites of Cen- 
tral France. From Filhol Rech, s. les Phosph. de Quercy 
two of these the incisors have their usual atin and space. 
One of these Tricentes Cope, has large canines well separated. It 
is uncertain whether the genus should not really be referred to 
the Creodonta.' It contains three or four rather small species from 
the Puerco formation of New Mexico. In Necrolemur the canine 
is insignificant. One species of the genus, the W. antiquus Filhol, 
is known. It is represented by a cranium in excellent preserva- 
_ tion (Fig. 8) which has been fully investigated by Filhol. This 
. able Se regards it as most nearly allied to the genus 
= now existing in Africa. It furnishes conclusive evidence 
SE ke former existence of lemurs in France. 
 1See NATURALIST, 1884, p. 353. 
