SOUTH 
1. Whalebone Whales (Mystacoceti) 
Right whales (Balcenidce) Rorquals {BalcenopteridcB) 
I I 
Southern right whale | | 
{Balcena glacialis) Finner whales Humpback 
{Ba Icev optera ) {Megaptera nodosa ) 
Blue whale {B, musculus) 
Tin whale (J5. physalus) 
Sei-whale {B, borealis) 
Piked whale {B, actitorostrala) 
Bryde's whale {B. brydei) 
2. Toothed Whales {Odonloceti) 
Sperm-whale Beaked whales Dolphins 
(Physeier catodon) (including bottlenose whales) (1) Killer 
{Hyperoodon rostrahis) (Orcimis area) 
(2) Black Fish 
(Globicephalus rnelas) 
(3) Porpoises 
{LagenorhyncJms sp.) 
The subdivision of whalebone whales is one of degree in the size 
of the whalebone. These whales have enormously muscular tongues, 
which press the water through the whalebone lamelte and thus, by a 
filtering process, retain the small food organisms. The food of the 
whalebone whales is largely the small Crustacea which occur in the 
plankton, though some whales (humpback, fin whales, and sei- whales) 
feed also on fish. The stomachs examined at South Georgia during 
December 1914 belonged to the three species, humpbacks, fin 
w^hales, and blue whales, and all contained small Crustacea— ^?/jjAa^t- 
sice, with a mixture of Amphipods. The toothed whales— sperms 
and bottlenoses — are known to live on squids, and that there is 
an abundance of this type of food in the Weddell Sea was proved 
by an examination of penguin and seal stomachs. Emperor 
penguins (and hundreds of these were examined) were invariably 
found to contain Cephalopod *' beaks," while large, partly digested 
sqtiids were often observed in Weddell seals. A dorsal fin is present 
in the rorquals but absent in right whales. With other characters, 
notably the size of the animal, it serves as a ready mark of identifi- 
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