CHAPTER IV. 
THE COMMON FINBACK, BALZNOPTERA PHYSALUS (Liny.). 
This species is the “Common Finback” of European waters. Hundreds 
of individuals have been taken at the Finmark whaling stations since 1874, and 
scores have been recorded as stranding at various points on the coasts of Europe 
during the 18th and 19th centuries. The species has been, on this account, 
more carefully studied than any other Finback. Sars’s diagnosis of the species, 
published in 1878 (79, 17), is as follows: 
“ Length of full grown individuals reaching to 70 feet. 
“Body slender; the greatest height scarcely exceeding + the length; behind 
the navel very much attenuated, the posterior half very narrow and maintaining 
almost the same depth throughout. 
“Color above and on the left side of the lower jaw dark gray, below white ; 
color of the back descending obliquely behind the pectoral fins so as to leave only 
a narrow median longitudinal area (below) along the posterior part of the body. 
“Mouth equalling about 1 the length of the body; upper jaw seen from above 
very narrow, wedge shaped, gradually decreasing in width toward the apex. 
“Pectoral fins small, scarcely exceeding 4 the length of the body, narrowly 
lanceolate, with the posterior angle often but little distinct ; the external surface 
showing the color of the back, the internal surface and the whole anterior margin, 
white. 
“Dorsal fin quite high, triangular, with the scarcely curved apex directed 
obliquely backward ; situated behind a vertical line drawn through the anal orifice. 
“Caudal fin uniformly white below, with the margins dusky. 
“ Whalebone dull bluish, varied with lighter color; some near the apex [of the 
upper jaw] white.” 
The admirable figure accompanying Sars’s article (plate 2) agrees exactly with 
the diagnosis. It represents the right side of the whale, showing the lower jaw 
and the anterior whalebone white, a character of importance, as will appear later. 
Sars’s diagnosis in Norwegian is somewhat fuller than that in Latin, which is 
translated above, and may be profitably included here: 
“Length of full-grown individuals reaches to 70 feet. 
“Body of especially slender and attenuated form, with the greatest height 
never exceeding 1 the total length, back of the navel suddenly and strongly di- 
minishing, so that the whole of the posterior portion of the body becomes unusually 
small and almost everywhere of one height as far as the root of the flukes. 
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