198 Proceedings of the Royal Society of Edinburgh. 



unrltT the throat and chest." He thinks the present specimen quite 

 distinct, specifically from the " Great Rorqual," (the Balaena boops, 

 jubarte, musculus, &c.), and not as M. Cuvier seems to think it, a 

 mere variety. Among other distinctions, the Great Rorqual has 13 

 dorsal, and 43 lumbar, sacral, and caudal vertebrae ; while the indivi- 

 dual now under consideration has only 1 1 of the former, and 36 of 

 the latter. There are, therefore, at least two species of Rorquals in- 

 habiting the North Seas, viz. the Great Rorqual, and the one now 

 under consideration, a specimen of which was described by Fabricius 

 (Balaena rostrata) ; another dissected by Hunter, and a third casually 

 observed by James Watson, Esq., who sent a drawing of the same to 

 Dr Traill, by whom it was communicated to ]Mr Scoresby. 



The author had not leisure to examine the osteology with sufficient 

 care ; the following results have, in the mean time, been attained. 



Internal and External Character. — Eight distinct bristles, ar- 

 ranged in perpendicular rows, were found in the extremity of the 

 snout, in both jaws. The lower part of the mouth is a huge pouch, 

 which, in the Great Rorqual, must at times contain a vast volume of 

 water. The tongue was free towards the apex ; and the inside of the 

 mouth of a pale rose or vermilion colour. 



The whalebone was about 2^ inches in length, varied from a pale 

 rose colour to a dull white, and 014 large external plates were count- 

 ed. No vestiges of teeth were found in either jaw ; but it is not im- 

 probable that they exist in the foetus of this species, as well as in that 

 of the Mysticetus, in the lower jaw of which, lying imbedded below 

 the gum, a series of teeth was discovered by M. Geoffroy St Hilaire 

 several years ago ; and in which the author of this paper has since ob- 

 served them in the tipper jaw. 



Brain and Nervous Systein. — The cranium, besides containing the 

 brain and its membranes, incloses a very large mass of a vascular sub- 

 stance, closely resembling an " erectile tissue." This forms an ex- 

 ception to the hitherto uniformly observed law of coincidence, at 

 least in the ^Mammalia, between the configuration of the inner table 

 of the skull and the contained brain. The erectile tissue filled a 

 large proportion of the interior of the cranium, also three-fourths of 

 the spinal canal, where it surrounded the spinal marrow and nerves; 

 being in some places nearly two inches in thickness. The whole ce- 

 rebral mass, comprising two inches of the spinal chord, weighed 3^ 

 pounds; while the cerebellum, pons, and two inches of the chord, 

 weighed only three-fourths of a pound. 



Rcxpiratorij Organs. — The mode of breathing, and the structure 

 of the nostrils, was precisely as in the Great Rorqual. Two bolster- 

 like substances filled the nostrils, which are withdrawn from them 

 at the moment of breathing by muscles provided for that purpose. 

 There are turbinated bones in the nose and olfactory nerves, as 

 large at least as the human. The author thinks it impossible for 

 water to be habitually spouted through the nostrils. The Whalebone 

 Whales have complex nostrils, and smell and breathe precisely as 

 the higher orders of the JMammalia. 



The Stomach, composed of four compartments, contained no food. 

 The middle tunic of the ureter was composed of distinct longitudinal 

 muscular fasciculi. 



