THE COMMON RORQUAL 
impetuosity that the line was broken by the resistance of the buoy as soon 
as it was thrown into the water, and the latter was liberated within a minute 
by the division of the line, occasioned, it was supposed, by its friction 
against the dorsal fin. 
" Both of them escaped. Another physalis (Rorqual) was struck by one 
of my inexperienced harpooners, who mistook it for a mysticetus. It dived 
obliquely with such velocity that 480 fathoms of line were withdrawn from 
the boat in about a minute of time. This whale was also lost by the 
breaking of the line." 
The Common Rorqual feeds on herrings and other fish as well as on 
crustaceans and squids. 
RUDOLPHI'S RORQUAL. 
Balanoptera borealis. Lesson. 
Plate 44. 
The Sei-Whale (Saithe- Whale), as this species is called by whalers, 
was first described by the Italian naturalist Rudolphi from a specimen 
taken in the Baltic in 1819. It is smaller than the Common Rorqual, 
full grown specimens measuring between 50 and 60 feet in length and 
occasionally more. 
The flippers are relatively short, the dorsal fin high and falcate and 
placed well forward on the body. 
Rudolphi's Rorqual varies considerably in colour. 
Mr. Millais says [Mammals of Great Britain and Ireland), " The 
majority are dark sepia suffused with grey like H. musculus. The colour 
of the under surface is grey with large irregular patches of white, the 
parts about the throat and genital organs white, from thence backwards 
to the flukes grey." 
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