MONODON.] MAMMALIA CETACEA. 43 



very young specimens, and falling in advanced life ; average number from 

 twenty-two to twenty-four in all. Skin smooth, of a deep bluish black 

 colour, with the exception of a whitish band beneath the body extending 

 from the throat to the anus. 



Common in large herds oif the Orkney and Shetland Islands. 



(3. DELPHI NAPTERA, Lacep.) 



68. D. albicans, Fab. (Beluga.) Head blunt : teeth 

 about nine on each side above and below ; short, with 

 obtuse summits. 



D. leucas, Desm. Mammal, p. 519. Delphinaptera albicans, Flem. 

 Brit. An. p. 36. Beluga, Barclay and Neill in Wern. Mem. vol. in. 

 p. 371. pi. 17. Scoresby, Arct. Reg. vol. i. p. 500. pi. 14. 



DIMENS. Entire length from twelve to eighteen feet. 



DESCRIPT. Body thick in the middle, somewhat tapering towards 

 each extremity, but more especially towards the tail : head small, blunt, 

 and round; the forehead rising abruptly: eyes and mouth small: jaws 

 equal : teeth in the adult state about nine on each side above and below, 

 short, straight, slightly compressed, with obtuse summits ; those in the 

 upper jaw falling in advanced life : a longitudinal ridge on the back sup- 

 plying the place of the dorsal fin : pectorals short, broad, and oval. Skin 

 smooth : colour wholly white ; sometimes with a tinge of yellow. 



A native of high Northern latitudes, where it is found in herds of 

 thirty or forty together. Must be considered as a very rare visitant of 

 the British seas. The individual described by Mr. Neill 1. c. was taken 

 in the Frith of Forth in June 1815. 



GEN. 28. MONODON, Linn. 



69. M. MonoceroS) Linn. (Narwhal.) Body sub-conical, 

 with a dorsal and ventral ridge : head obtuse, about one- 

 seventh of the entire length. 



M. Monoceros, Scoresby, Arct. Reg. vol. i. p. 486. pi. 15. Flem. 

 Brit. An. p. 37. Small-headed Narwhal, Flem. in Wern. Mem. 

 vol. i. p. 131. pi. 6. 



DIMENS. Entire length, exclusive of the tusk, thirteen to sixteen 

 feet ; circumference (at the thickest part) eight to nine feet ; length of 

 the tusk about five feet*. 



DESCRIPT. Anterior half of the body nearly cylindrical; posterior 

 half conical: this latter portion furnished with a dorsal and ventral 

 ridge, which take their origin about three feet from the extremity, and 

 extend half way across the tail ; the edges of the tail run in like manner 

 six or eight inches along the body, forming ridges on the sides of the 

 rump : head about one-seventh of the entire length ; small, blunt, and 

 round ; the forehead very prominent, rising suddenly from the snout : 

 mouth small; intermaxillary bones furnished each with one tooth di- 

 rected forwards; in the female these teeth generally remain through 

 life concealed in the sockets, not appearing externally ; in the male, 

 that on the left side is exserted, growing to the length of several feet; 



* The above measurements are from Scoresby, from whose excellent work on the Arctic 

 Regions much assistance has been derived in drawing up the characters of this species, as well 

 as of some others of the Cetacea. 



