440 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 
Dr. Ely states that in the older and larger American skulls, both orbital 
processes are strongly developed, in many skulls the posterior one being as 
strongly marked as in the European, a statement I find confirmed by my own 
series. In the American skulls, he finds the position of the postorbital proc- 
ess, in respect to the highest point of the malar bone, to be as stated by 
Brandt, but records one exception to even this difference. 
“(3) The snout,” says Brandt, ‘‘measured from the inferior orbital open- 
ing to the inferior corner of the nostril in two European skulls of equal size 
(Nos. 56 and 106 of the Kiew Coll.) is broader and somewhat longer than in 
an American skull in the Academic Museum.” 
(4) ‘The nasal bones,” Brandt continues, ‘show the greatest variations. 
Their length in all the European is much above one-third the length of the 
skull, measured from the incisor teeth to the crista occipitalis; while, on the 
contrary, in the three larger of the American skulls the length of the nasal 
bones is only a little if any over one-third, and the smallest not even one-third 
the length of the skull. The nasal bones of the six older skulls lying before me 
of the Kuropean Beaver are therefore longer, and extend more or less far pos- 
teriorly, 2. e. more or less beyond the anterior prominence of the arch of the 
eyebrows, so that they (the nasal bones) lie with their posterior borders 
nearly or quite opposite the middle of the margin of the orbits. In a young 
Polish Beaver (No. 57 of the Kiew Coll.) they reach, however, only to the 
anterior third of the orbital ring, and in our young Lapland Beaver they lie 
nearly as in our California Beaver skull, opposite only the circumference of 
the anterior border of the orbital ring. In none of five American skulls, 
lying before me, on the contrary, do the nasal bones extend beyond the ante- 
rior prominence of the eyebrows. In nearly all the skalls of the European 
Beaver, compared with the five American ones lying before me, the nasal 
bones are in form longer in the middle and posterior, however, in general nar- 
rower, so that their breadth in their middle varies between one-fourth and 
one-fifth of their length, while in our five American skulls the breadth of 
their middle portion attains to between one-third and one-fourth of their 
length. Although the nasal bones of the American beaver are thus on the 
whole broader, still they vary less in this respect than in their lesser length. 
The external border of the nasal bones of the European Beaver is not so 
strongly curved as in the American. Two of the European skulls, however, 
approach quite to the,American in this respect. The superior surface of the 
