KNOX ON THE CETACEA. 75 



nostrils of the Dolphins is wholly wanting in the Balsena "Whales, — 

 a fact of which M. Cuvier was not aware when he wrote his cele- 

 brated Treatise on Comparative Anatomy. 



Appendioc. — Since writing the above, I have received an answer 

 to a letter I addressed to my friend, John Groodsir, Esq., Professor 

 of Anatomy in the University of Edinburgh. The request con- 

 tained in my letter to Mr. Groodsir was, to examine for me the 

 skeleton of a foetal Mysticetus now in the University Museum. 

 The foetus from which this skeleton was prepared was removed 

 from the uterus of the mother, killed in the North Seas by the 

 seamen of a whaling ship, by one of my former students, Mr. E. 

 Auld, who presented the specimen to me. The point at issue was 

 the composition of the cervical vertebrae in the true or Greenland 

 "Whale, the Balcena Mysticetus. M. Yan Beneden, to whose 

 memoir I have referred in the commencement of this, says, on the 

 authority of Eschricht, that at no age whatever do we find in true 

 Whales (meaning, I presume, the Mysticetus horealis and australis) 

 any distinct vertebrae in the cervical region, as in other mam- 

 mals. A fusion of all into one bone or cartilage seems to take 

 place even in the youngest foetus. Now, I had enjoyed the rare 

 opportunity of dissecting the foetus of the Mysticetus, and I knew 

 that the skeleton, prepared with the greatest care, was still pre- 

 served in the Museum of the University of Edinburgh. I wrote 

 to Mr. Goodsir to re-examine this point for me, for I did not find 

 in my notes any confirmation of the observations of Eschricht. 

 Mr. Goodsir' s reply to my note is as follows : — 



" University, Edinburgh, 

 " My dear Sib, ^^P*- ^0' 1857. 



" In the skeleton of the foetal Mysticetus now in the University 

 Museum, the bodies of the axis and atlas have shrivelled up toge- 

 ther, having evidently consisted of cartilage only ; but the bodies of 

 the five posterior cervical vertebrae are beautifully distinct, having 

 well-formed osseous centres, which give them more of the con- 

 figuration of the succeeding vertebral bodies than they present 

 in their compressed form in the adult. 



" The neural arches in the cervical region of this skeleton are 

 five in number ; the two anterior, which are distinctly those of 

 the atlas and axis, have an osseous nodule on each side, where the 

 transverse processes pass off". The third arch belongs to the third 

 vertebra, the fourth and fifth to the sixth and seventh. These 

 three arches are cartilaginous, and present no osseous centres. It 



