222 PROFESSOR TURNER'S ACCOUNT OF THE GREAT FINNER WHALE 



comparison may be found in the well-marked vascular folds of mucous mem- 

 brane, covered by epithelium, which lie transversely across the palate in the 

 Ruminantia. In the giraffe, for example, these folds are very strong, and they 

 are, moreover, fringed along the free edge with well-defined papillae, which are 

 also covered with an epithelium. If we were to suppose these papillae con- 

 siderably elongated, their epithelium cornified, and the whole series of papillae, 

 springing from any single fold, bound together by a cortical, cornified, epithelial 

 layer, we should then have an arrangement of parts closely corresponding in 

 structure to that of a plate of whalebone. But the Balaenoidea are not the only 

 placental mammals in which a cornified epithelium is developed in connection 

 with papillary growths from the surface of the buccal mucous membrane. For, 

 as is well known, in the Carnivora, the papillae on the dorsum of the tongue are 

 invested with a horny epithelium arranged in the form of retroverted spinules. 



I am also of opinion that we must assign to the baleen a more important 

 function than that of the mere hair sieve or filter, with which it is most usually 

 compared. For structurally it is much more highly organised than hair. It is 

 highly vascular, and, I believe, also nervous, and can therefore play the part of a 

 whole series of tactile organs, by means of which the animal would be enabled 

 to estimate the amount and character of the food which it receives into the 

 cavity of the mouth. 



As Geoffrey St Hilaire* and Robert KNOXt had discovered rudiments of 

 the teeth in the gum of the very young foetus of the Balcena mysticetus, and as 

 EschrichtJ had also observed them in the fcetal stage both of Megaptera and 

 Balcenoptera, I removed the gum from the edges of both the upper and lower 

 jaws, with the view of examining if the rudiments of these organs still existed 

 in the almost fully developed foetus of the Longniddry Finner. I found in con- 

 nection with the periosteal surface of each gum a well-defined band, which 

 corresponded precisely with the margin of the jaw, and which received a number 

 of arteries coming through foramina in the bones. This band, from its position, 

 was obviously the part in which the teeth, if present, ought to have been found. 

 A careful examination, however, both of the band and of the tissue on each 

 side, failed to discover the smallest rudiment of a tooth. Hence it follows that 

 in the Balaenoidea not only do the teeth not pierce the gum, but all trace even 

 of their rudiments disappear before the termination of foetal life. 



Alimentary Organs. — Owing to the wide sweep of the lower jaw, the cavity 

 of the mouth was of great size, and the space included between the two halves 

 of the lower jaw reminded one of a huge barge ; indeed it was no uncommon 



* Aimales du Museum. Vol. x. p. 364. 



f Catalogue, op. cit. p. 22. Knox's preparations are in the Anatomical Museum of the University 

 of Edinburgh. 



t Die Nordischen Wallthiere, 1848. 



