REVIEWS. 41 
. the eared seals proposed by this author in his above-cited paper. 
While still agreeing with him in regard to the comparatively wide 
separation of Zalophus from its nearest allies, and in regard to its 
being intermediate between the fur and other hair seals in respect 
to size, but only in this point, I am compelled to still differ with 
him in respect to its constituting a primary group coordinate with 
that of all the other eared seals.* Whilst a somewhat aberrant 
form, it seems to me to be by no means very far removed from 
Eumetopias and Otaria. I can, in fact, scarcely comprehend how 
it has happened that the author in question has overlooked the 
presence of a well developed sagittal crest in all the genera of 
the Otariade except Zalophus, as he seems to have done in the 
differentiation of his two primary groups of this family. The 
supposition that he has examined only the skulls of females or 
young males of the other genera is hardly sufficient to explain this 
oversight, since figures indicating its presence in the males of the 
other genera have been long published, to say nothing of the many 
distinct allusions to it by authors. While familiar with the distinc- 
tive characters of Zalophus, he has failed to indicate them in his di- 
agnoses, the comparatively unimportant character furnished by the 
rostral outline being far less characteristic than its slender elon- 
gated muzzle and other features, which had previously been well 
pointed out by Dr. Gill, as well as by other writers. The sagittal 
crest reaches, it is true, its maximum development in Zalophus; 
but any one who has seen the high sagittal crest possessed by old 
males of Eumetopias Stelleri, in which as a thin solid plate it at- 
tains the height of 38 mm., or an inch and a half; and the rela- 
tively scarcely less developed sagittal crest in old males of Callo- 
rhinus ursinus; and the figure of old male skulls of Otaria jubata, 
and some of the species of Arctocephalus, in which a high sagittal 
crest is represented; cannot but be surprised to find in what is - 
assumed to be an enumeration of ‘‘the most obvious and dis- 
tinctive characters” of the genera Callorhinus, Arctocephalus, 
Otaria and Eumetopias, a diagnosis contrasting “‘ a sagittal groove 
from which are reflected the low ridges indicating the limits of the 
temporal muscles” in these genera, with ‘‘a solid, thin, and much 
elevated sagittal crest” in Zalophus! The females of Callorhinus 
ursinus and Otaria jubata, and, so far as at present known, of all 
*See American Naturalist, Vol. IV, p. 681. 
