DH. J. MURIE ON THE ORGANIZATION OF THE CAAING WHALE. 243 



his with regard to the structures. He looks upon the whole only in the light of a 

 mechanical apparatus, and shows that the adjustments are such that " when the outer 

 passage is closed, the posterior pouches can be distended and the anterior are emptied ; 

 and when the passage is open, the anterior pouches can be distended and the posterior 

 are emptied." He believes the pouches serve to buoy up the head, and considers the 

 spouting of the Whale to be sea-water regurgitated from the stomach. 



Stannius' alludes to only a single muscle connected with the nasal sacs and spout-hole ; 

 this he calls the nasalis. He apparently disregarded the separation into layers of the 

 muscular constituents surrounding the outer naris and its pouches. He describes, more- 

 over, a musculus cutaneus maxilla? superioris — to wit, the long premaxillary muscle 

 covered by the blubber (Nl of my plates) ; but as this is posteriorly interwoven with 

 the buccinator, he includes it under the cheek-muscles. 



With the exception of Hunter's^ lucid physiological deductions as to the use of the 

 nasal sacs, Von Baer's paper' is by far the most philosophical description and piece of 

 reasoning treating of this curious Cetacean apparatus. In it he notices the existence 

 of a small single bone near tlie intermaxiUaries, which Camper believed to be a process 

 of the ethmoid, though other anatomists have overlooked it. Von Baer regards this 

 little bone as a rudimentary inferior turbinate. There are cartilages present which he 

 considers represent the blade of the ethmoid and not the vomer. 



He goes on to say that Cuvier only takes notice of two nasal sacs. Camper and Eay 

 thought there were three, while Blainville speaks of two pairs. He then gives a 

 description of the sacs as they in reality exist in the Porpoise, and of the external layers 

 of muscles. He states these may be divided into as many as six portiQns, which, 

 however, he is inclined to regard as but one entire layer infolded upon itself. He 

 pointedly observes, moreover, that they have a general resemblance to the nasal 

 muscles of Man. There is, he thinks, no special sphincter to close the blow-liole, 

 as the lips are thick and close together by their own elasticity. According to Blainville 

 the sacs have three pairs of muscles acting upon them. Von Baer criticises Cuvier 

 and others who say the muscles press upon the spout-hole to eject water therefrom, 

 whereas he reasons upon his examination and known data to show that view is not 

 tenable. From smell and inspiration of air having but a single passage. Von Baer 

 believes the former is subdued. 



He further discusses the number and position of the turbinal bones in various orders 

 of animals, and shows that the anterior one in them has been taken for the upper one 

 in Man, whereas he avers this is not the case. Gurlt, as he mentions, calls it the 

 middle turbinal bone. Von Baer himself admits, however, that the turbinals are not 

 specially organized parts— in other terms, are irregular in construction. He endeavours 

 to show in different genera of Cete that the blow-hole influences the formation of the 



' L. c. p. 4; and Rapp, p. 106. ' L. c. p. 335. 



^ "Der Nase der Cetaceen," Isis, 1826, p. 811. 



VOL. VIII. — PART IT. February. 1873. 2 n 



