Owen— Observations on the Zeuglodonts. 407 
the anterior walls indicate an oblique direction ; whilst in the skull 
from Barie the nasal passage is vertical: no trace of nasal bones 
remains. 
M. Van Beneden states, ‘Les os palatins sont disposés comme dans 
les véritables Cétacés soufileurs: ils forment Ventrée des fosses 
nasales’ (p. 49). I have found the palatine bones, in true Cetacea, 
separated from the posterior or palatal nostrils by the pterygoids, 
which exclusively form that entry to the nasal passages. 
In the fossil skull of the Zeuglodont discovered at Barie, the 
nasals are compact bones, ‘en os compactes,’ situated above the blow- 
holes, ‘refoulés au-dessus des évents’ (p. 53). The intermaxillaries, 
which exclusively form the end of the snout, extend thence backward 
to the nasal bones. ‘The maxillaries posteriorly cover the frontals 
and reach the vertex : the frontals are very thick above the orbits : 
the malar is extremely slender. The occiput is flattened behind, 
rises also to the vertex, and forms there a crest which trends the 
occipital region : it is narrow behind. 
The petrotympanics resemble those of Zeuglodon. The atlas- 
vertebra in the European Zeuglodonts, as in the American, is sepa- 
rate from the other cervicals. Prof. Van Beneden remarks that the 
Balznoptere, certain Delphins, e. g., the Belugas and Narwhals, and 
the Sirenia (Manatees and Dugongs), are among the small number 
of Cetacea in which the atlas is not anchylosed to the other 
vertebra (p. 46). But to this list may be added the large Cachalots. 
The atlas from the ‘Faluns de Salle,’ figured by Van Beneden in 
pl. iii., fig. 2, ‘offre une grande analogie avec l’atlas de Zeuglodon 
que Joh. Miiller a décrit et figuré dans son grand travail sur les 
Zeuglodontes d’ Amérique’ (p. 47). 
M. Van Beneden assumes that the nasal bones in all the Euro- 
pean Zeuglodonts correspond with the condition of these bones in 
the mutilated portions of skull described by Jourdan, and regards 
the longer, perhaps more perfectly preserved, ‘nasal’ bones of the 
American Zeuglodont as justifying a generic distinction. He even 
goes so far as to conjecture that the American Zeuglodonts, not- 
withstanding their bulk, which rivals that of the Whales, were 
carnivorous Cetacea haunting the shores, like the herbivorous 
Dugongs and Manatees, whilst the smaller European species were 
pelagic carnivora like the Grampuses and Porpoises. ‘Les Zeu- 
elodons, malgré leur taille, seraient done des carnassiers littoraux, 
comme les Siréniens des herbivores littoraux, et les Squalodons 
seraient des carnassiers pélagiques’ (p. 63). But the deposits in 
Alabama and Louisiana containing Zeuglodont remains are strictly 
marine. ‘The external nostrils of these large Zeuglodonts open in 
the upper part of the skull, far behind the end of the snout : some 
difference in the direction of the nasal passages is admitted by 
Van Beneden to exist in the European Zeuglodonts, as, e. g., between 
the Squalodon Ehrlichit, Van Beneden, and the Stenodon lentianus, 
V. B. 
We doubt whether, from present materials, so trenchant a dis- 
tinction can be relied on as generically differentiating the Zeu- 
