or 
DR. J. MURIE ON THE ORGANIZATION OF THE CAAING WHALE. 
bo 
4 
a careful survey of these structures has been instituted, it is unnecessary to pursue the 
subject here. I may add, though, that the sacs of Globiceps are three on either side, the 
so-called facial division of the naso-frontal being absent. All three genera, therefore, 
differ from Phocena in division of the anterior or slipper-shaped premaxillary cavity. 
The next structures whereby homology of parts can be traced are the cartilages. 
These, compared with the massive head, I may say, are very small, much interwoven 
with the fibrous and fatty tissues bordering the narial orifice, but nevertheless traceable. 
Shooting forwards from in front of and between the nasals as a narrow, short and diminu- 
tive wedge, is a little stump of cartilage, which I take to be the prevomerine ethmoidal 
or septal cartilage in a very rudimentary condition’. On each side of the above, partly 
continuous and partly connected by fibrous material, is another, irregular-shaped but 
somewhat curvilinear and small fibro-cartilaginous isthmus, but which I could not 
satisfactorily follow out. From position they would accord with the upper lateral 
cartilages of land Mammalia. Lastly, forward from these and only connected by fibroid 
tissues (I speak only as far as my dissection permitted me to observe) are the two much 
larger and transversely oblique masses, visible in the upper opening of the nares, and 
which are composed of fibro-cartilage fatty substance and mucous membrane. As bearing 
relationship to the above mentioned, these bodies, to my reading, are homologous with the 
alar cartilages and their mucous membranous covering, either in whole or in part. 
Now, if these fibro-cartilaginous masses collectively be rudiments of what I have said, 
even though I may have mistaken them individually, they afford a clue by which the 
muscular layers above can be understood aside from their office of dilators and com- 
pressors of the sacs and narial orifice. Furthermore the muscles and the cartilages 
furnish data expressive of what the nasal sacs are themselves. Von Baer builds up his 
homological theory of the Cetacean nasal sacs being the turbinate bones upon one 
gratuitous assumption, which if unsupported by other evidence than he has given, the 
whole structural pile of his reasoning falls baseless. I allude to the fact that he 
considers the thin fibrous induplicated membrane of certain of the rugose sacs an arrested 
condition of the osseous twisted lamin of the turbinals. In short, he takes for granted 
membrane replaces bone. As to this being the case, we have not a shadow of evidence. 
Indeed it is far more reasonable to suppose the ethmoidal turbinates aborted or entirely 
absent, than that they should be represented by or be transformed into a sacculate 
membrane of fibro-areolar consistence. It is undoubted that the Cetacea have singularly 
modified skulls. Some bones are very diminished in size, some wonderfully increased, 
and others jammed into most abnormal positions, or are unsymmetrical ; but I think it 
yet lacks positive proof that a membrane completely replaces an entire cranial bone in 
the adult cranium. 
Luckily for me, Von Baer compares the Porpoise’s nasal sacs with those of a calf, 
1 As bearing on the subject, consult Dr. Cleland’s well-reasoned paper “On the Relations of the Vomer, 
Ethmoid, and Intermaxillary Bones,” Philos. Trans. 1863, p. 289, pls. 4 & 5. 
2n2 
