12 
Proceedings of the Royal Society of Edinburgh. [Sess. 
of a Balsenoptera, which I have identified as similar in character to 
B. rostrata of the North Atlantic. 
BAL.ENOPTERA ROSTRATA. 
This species, known to fishermen as the Lesser Piked Rorqual, is the 
smallest and most frequent of the baleen whales stranded on the coast of 
Scotland.* It has not been, I believe up to now, recognised by zoologists 
as a species frequenting the South Atlantic. Mr Coughtrey, however, 
informed me that the whaling seamen engaged in the South Shetlands 
and Graham Land fishing are acquainted with a small baleen whale 
called by them Minim, which contrasted strongly in its dimensions with the 
Blue Whale, Sye Whale and Humpback. Its relatively small size, the 
thinness of its coat of blubber, and the short whalebone made it of so little 
commercial value that it was seldom captured. During the last whaling 
season one was shot, and a right adult tympanic bone, along with a well- 
grown fcetus, was preserved by Mr Coughtrey. From the study of these 
specimens I regard this cetacean as the species Balcenoptera rostrata. 
Tympanic Bone. 
The small size of this bone in rostrata at once distinguished it from the 
large tympanies of the other Balmnopteridse. I have carefully compared 
the South Atlantic specimen with the tympanies of this species from the 
North Atlantic in the Anatomical Museum. 
Length. 
Breadth. 
Height. 
B. rostrata — 
South Atlantic 
Elie, Firth of Forth 
1? 55 -5 • • 
Burntisland, „ „ . . 
Alloa ,, ,, (young) . 
3 '3 in., 85 mm. 
87 „ 
87 „ 
85 „ 
81 „ 
2 in., 50 mm. 
45 „ 
46 ,, 
44 „ 
2’2 in., 56 mm. 
55 „ 
56 „ 
56 „ 
1 
The South Atlantic specimen closely corresponded in dimensions to the 
tympanic bones of rostrata captured in the Firth of Forth, the somewhat 
greater breadth being due to the outer surface being a little more convex 
in the Southern specimen than in those from the North Atlantic. The 
configuration of the outer and inner surfaces of the tympanic, the appear- 
ance of the shallow inferior keel, the sharp ridge of the anterior border, 
the blunt posterior border, the sinuous character of the upper border 
* See my memoir on the Lesser Rorqual in Proc. Roy. Soc. Edin., vol. xix., 1892, in 
which several specimens are described. 
