1884.] The Amblypoda., IIIS 
The homologies of the parts of the teeth of the different gen- 
era of the Amblypoda are not determined without considerable 
study. The greatest difficulties are presented by the superior 
molars, and in order to understand them it is necessary to study 
the inferior molars first. 
If we compare the 
inferior molars of the 
Pantolambda cavirictus 
with those of the Bazh- __-— 
yopsis fissidens (Fig. 7) STA 
(one ofthe Dinocerata) be 
the following modifica- 
tions will be observed: 
(1) The two limbs of 
the anterior V in the 
true molar of the for- 
mer are represented in 
the latter by a single 
crest with two appress- 
ed apices at the inner 
extremity. These 
apices represent those 
of the two limbs of the 
V. (2) The posterior 
limb of the posterior V 
is much diminished in 
elevation, and does not 
Join its anterior limb 
at the apex on the ex- 
ternal side ofthecrown. 
we now examine the 
corresponding parts of 
another Dinoceratous 
Original, from 
Wind River (? Bridger) of Wyoming. From Vol, u1 Report U. S. Geol, Survey Terrs., F. V. Hayden, 
\ 
size, from above: a, from front, 
Fic. 7.—Bathyopsis fissidens Cope (one of the Dinocerata), mandible anterior to the coronoid process ; incisors and 
canines and first premolar lost from both sides, two-thirds nat, 
find the process carried 5 . h 
still further. The crown has only two crests which saa 
each other but do not join at the apex on the inner side. e 
