82 Mr. J. E. Gray on the British Cetacea. 



Mandibles nearly cylindrical, very long and prominent, widely 

 divergent at the extremities, which are armed with a long, slightly 

 curved dark brown fang, having a small, obtuse protuberance at 

 its base on the upper side ; on their inner surface are two rows 

 of teeth, the outer one consisting of twelve and the inner one of 

 eight ; they have, besides, seven strong tooth-like processes at 

 their extremity surrounding the base of the fang : maxillae long, 

 straight, enlarged at the extremity, which is prominent and some- 

 what angular on the outer side : these parts are yellowish brown. 

 Lip semicircular and dark brown, the apex, which is prominent, 

 being yellowish brown. Sternum of an elongated heart-shape 

 and brown colour. Cephalo-thorax somewhat oval, slightly com- 

 pressed before, broadly rounded in front, with a large circular 

 indentation in the medial line of the posterior region ; it is of a 

 brown colour with rays of a deeper shade diverging from the me- 

 dial indentation to the margins. Eyes disposed on black spots 

 in two transverse nearly parallel rows on the anterior part of the 

 cephalo-thorax ; the anterior intermediate pair, with each lateral 

 pair, is seated on a prominence, the anterior eye of the latter 

 being the smallest of the eight. Legs long, slender, provided 

 with hairs and a few fine spines ; they are of a pale brown 

 colour ; first pair the longest, then the second, third pair the 

 shortest. Palpi very slender and yellowish brown ; the cubital 

 joint is the shortest and after that the axillary joint. Abdomen 

 long, somewhat cylindrical, enlarged at its anterior and tapering 

 to its posterior part ; along the middle of the upper part extends 

 a large, festooned brown band whose margins are the darkest ; in 

 the medial line of this band are numerous, minute, whitish spots, 

 and four small indentations, forming an elongated trapezoid, 

 whose anterior side is the shortest, occur on the part which is 

 enlarged; sides dull yellowish brown, comprising an obscure, 

 irregular, longitudinal brown band ; under part dull yellowish 

 brown, with a dark brown band in the middle tapering to the 

 spinners, at the base of which, on each side, is a whitish spot, 

 Spinners and plates of the spiracles reddish brown. 



XII.— O/i the British Cetacea, By J. E. Gray, Esq., F.R.S. 



Having occasion lately to examine the various species of Cetacea 

 in the British Museum and other collections and the various au- 

 thorities for the species, I am induced to send you the following 

 list containing some additions to our fauna. It would appear as 

 though modern writers on this part of our fauna had not taken the 

 trouble to examine for themselves the authority on which the spe- 

 cies have been determined. Dr. Fleming, in his ' British Am- 



