204 DR. J. E. GRAY ON BRITISH CETACEA. [May 24, 
calls Rorquals a ventre lisse, and which Dr. Fleming transformed into 
a genus under the name of Physalus, very doubtful. 
Lacépéde referred to the smooth-bellied Rorquals the “ Hunch- 
back”? of Dudley, who distinctly says the belly is ‘‘reeved ;’”’ but 
Lacépéde did not understand that word to be synonymous with 
plaited. 
Sibbald (Balznologia Nova, 1692) figures two specimens of 
Finners, caught on the coast of Scotland. Ray (Hist. Piscium, 17) 
noticed these specimens. Brisson and Linnzeus regarded them as 
separate species. Linnzeus designated the one with the skin under 
the throat dilated, probably by the gas in the abdominal cavity, B. 
musculus, and the other with this part contracted and flat B. boops ; 
and these species have been retained by Turton, Fleming, Jenyns, 
and other authors who have compiled works on the British fauna, 
except Bell, who cut the Gordian knot by uniting them and the 
Balena rostrata of Hunter into a single species! The author who 
appears to have best understood the British species is Dr. Knox, 
who took some pains to examine these animals and their anatomy. 
It is only necessary to refer to Dr. Jacob’s very interesting paper 
in the ‘Dublin Journal of Science’ for 1825, p. 332, where he 
attempts to prove that all the Finner Whales found in the North 
Sea are of one species. To show how dangerous it is to reason on such 
subjects, his arguments are scattered to the wind directly that a 
reference and comparison is made to specimens. The examination 
and comparison of the skeleton, after making every allowance for 
changes which may take place in the development of the bones 
during the growth and the variations that may occur in individuals 
of the same species, show that the species of Finner Whales which 
inhabit the northern hemisphere are much more numerous than was 
formerly suspected ; and it is probably the same with those that in- 
habit the southern half of the globe. 
Professor Eschricht, in 1846, had so little confidence in the number 
of species of Whales inhabiting the North Sea that he considered 
that he had made an advance when he thought it was proved that 
there were at least three different species having their abode in the 
North Sea (4th Mem. p. 157). 
Cuvier, in his essay in the ‘ Ossements Fossiles,’ admits three kinds 
of Finner; each of them now forms the type of a genus: Rorqual du 
Cap=Megaptera; Rorqual de la Méditerranée= Physalus ; Rorqual 
du Nord=Sibbaldus and Balenoptera. Van Beneden, in 186], 
progresses one step further; he admits four—that is, separates the 
Rorqual du Nord into two species: thus,—1. Pterobalena minor= 
Balenoptera; 2. Pterobalena communis=Physalus (and perhaps 
Benedenia) ; 3. P. gigas=Sibbaldus ; 4. Kyphobalena longimana= 
Megaptera. (See Nouv. Mém. Acad. Roy. Brux. 1861, xxxii. 38.) 
I. Dorsal fin low, broad. Pectoral fin elongate, with four long 
fingers. Blade-bone broader than high, with only a small or no 
coracoid process. Cervical vertebre often anchylosed. Frontal 
bone broad, narrowed at the orbital end; orbit moderate. 
