xv FORE LIMBS 223 



undivided covering of skin, which allows externally of no sign 

 of the separate and many-jointed fingers seen in the skeleton. 



Up to the year 1865 it was generally thought that there 

 was nothing to be found between this bony framework and the 

 covering skin, with its inner layer of blubber, except dense 

 fibrous tissue, with blood-vessels and nerves sufficient to 

 maintain its vitality. Dissecting a large rorqual, 67 feet in 

 length, upon the beach of Pevensey Bay in that year, I was 

 surprised to find lying upon the bones of the forearm well- 

 developed muscles, the red fibres of which reached nearly to 

 the lower end of these bones, ending in strong tendons, 

 passing to, and radiating out on, the palmar surface of the 

 hand. Circumstances then prevented me following out the 

 details of their arrangement and distribution, but not long 

 afterwards Professor Struthers, of Aberdeen, had an opportunity 

 of carefully dissecting the fore-limb of another whale of the 

 same species, and he has recorded and figured his observations 

 in the Journal of Anatomy for November 1871. He found 

 on the internal or palmar aspect of the limb three distinct 

 muscles corresponding in attachments to the flexor carpi 

 ulnaris, the flexor profundus digitorum, and the flexor longus 

 pollicis of man, and on the opposite side but one, the extensor 

 cornmunis digitorum. 1 Large as these muscles actually are, 

 yet, compared with the size of the animal, they cannot but be 

 regarded as rudimentary, and being attached to bones without 

 regular joints and fijrmly held together by unyielding tissues, 

 their functions must be reduced almost to nothing. But 

 rudimentary as the muscles of the fin-whales are, lower stages 

 of degradation of the same structures are found in other 

 members of the group. In some they are indeed present in 

 form, but their muscular structure is gone, and they are 

 reduced in most of the toothed whales to mere fibrous bands, 

 scarcely distinguishable from the surrounding tissue which 

 connects the inner surface of the skin with the bone. It is 

 impossible to contemplate these structures without having the 

 conviction forced home that here are the remains of parts once 

 of use to their possessor, now, owing to the complete change of 



1 The muscles of the forearm of an allied species, Balcenoptera rostrata, were 

 described by Macalister in 1868, and Perrin in 1870. 



