128 ON A FEMALE SPECIMEN OF THE COMMON RORQUAL 



Beige, Avril, 1884, p. 365) mentions that the asymmetry noted by 

 Prof. Sars in B. niusculiis does not exist in B. /wrea/is, and adds in a 

 note, " Cette couleur l)lanche, semi-laterale, que M. le Professeur 

 G. O. Sars a deja decrite, n'est pas exclusivement attachee a un cote 

 special, mais elle varie d'apres les observations que j'ai faites." I 

 am not aware of his having published any fuller information on this 

 interesting point. 



In 1886, Prof M. G. Pouchet of the Paris Museum, in a very 

 interesting memoir " De L'Asymetrie de la Face chez les Ceto- 

 dontes,'"" dealing chiefly with the osteological differences in toothed 

 whales, mentions the asymmetry of colour in B. miisculus recorded 

 by Sars and Guldberg as a kind of pleuronectism, and adds : — 



Si cette decoloration existe toujours du coi^ droit comme semble I'indiquer 

 Sars, elle constituerait pour les Balrenides une sorte de caractere abdominal^ de 

 meme que la deviation de I'^vent des Cetodontes donne chez eux au cot^ gauche 

 une sorte de caractere dorsal. Un lien physiologique semblerait en ce cas relier 

 les deux particularit^s auatomiques, qui Tune et I'autre accuseraient une ten 

 dance au pleuronectisme du meme cot^." 



In the Burnham specimen, not only is the asymmetry well 

 marked, but a curious deviation obtained. On the right side, as 

 may be seen in the illustration, a portion of the upper maxilla vary- 

 ing from I to 7 inches, about 2ft. of the baleen, and a curved margin 

 varying from 5I inches on the band of the lower jaw, being white, 

 whilst below this the throat is black, which colour extends in an 

 oblique line to the base of the pectoral flipper. 



Why this species should exhibit such a remarkable feature, which 

 appears to be common also to both sexes ; and of what particular 

 use it can be to the animal is not known, nor does it seem possible 

 at present to advance any likely reason for the peculiarity. 



In conclusion, I may mention that the flesh was used for 

 manurial purposes at Southminster, that the bones are now being pre- 

 pared by Mr. E. Gerrard, of Camden Town, for the owners, and the 

 skeleton will probably be articulated for exhibition at Burnham. 



3 Prof. Pouchet very kindly sent me a copy of this rare Memoir, which he was deputed to 

 write and publish by the Nat. Hist. Mus. of Paris, in honour of the professorial jubilee of the 

 veteran cetologist, Van Beneden, Professor of the University of Louvain, whose works on the 

 osteology of living and fossil cetacea, and other writings, are so well known to naturalists. 



