1885.] Geology and Paleontology. 703 
an annectant group, pointing to the existence of some extinct 
group which may have still more closely connected the sessile- 
eyed and stalk-eyed Crustacea——A. S. Packard. 
MARSH ON THE D1noceraTA.'— This work, which has been an- 
nounced for some time, is now before us. It is one of the quarto 
series of the United States Geological Survey, but the present 
edition was published, we are informed, by the author at his own 
expense. The mechanical execution of the book is good, and it 
will remain a monument to its authors. We confess, however, to 
surprise at not finding it, as we had anticipated, a monograph of 
the group. According to the synopsis of twenty-nine reputed 
material representing them has been obtained by Professor Marsh, 
but we have searched in vain for a description of the greater part 
of it in the work. The memoir is in fact of a rather general 
character, giving descriptions of the osteology of the two species 
Loxolophodon mirabile and L. ingens,’ with occasional references 
to others. It is evident that the greater part of the work of 
writing this monograph remains to be done. We should have 
preferred to have seen this magnificent opportunity improved, so 
that it should have embraced detailed aaah aus of those char- 
acters of all the species on which alone the derivation theor 
can be established or refuted. A taral result of this neglect 
is a failure to appreciate the true generic relationships of the 
species. There are no sufficient characters adduced for the gen- 
eric discrimination of the species included under the heads 
Dinoceras and Tinoceras, while the characters of Uintatherium 
are erroneously given. The distinct genus Bathyopsis is not ad- 
Professor Marsh thinks that the females of these animals had 
shorter canine teeth than the males, and that the protective man- 
dibular flange is correspondingly small in that sex. He also finds 
istana in the nasal tuberosities, and indicates that these also 
rger in male animals. 
re connection with the description of the brain of the Dinocerata, 
ever, fails to give Professor Lartet credit for the proposal of the 
general theory of brain development in the Mammalia with the 
progress of geological time 
The classification of. the Ungulata adopted is largely that of 
Cope, to whom no acknowledgment is made. A hypothetical 
group is proposed and defined as the primitive type of Ungulata. 
1 The Dinocerata, By O. C. Marsh. 
3 For the genera of Dinocerata, see NATURALIST, June, 1885. 
