FIELD BOOK OF MAMMALS 



Genus Sibbaldus 



Sulphur-bottom Whale. — Sibbaldus musculus 



(Linnaeus) 



Names. — Sulphur-bottom Whale; Blue Whale; Sibbald 

 Whale. 



General Description. — Largest of all the Whales, reaching 

 a known length of 103 feet (average length 60-80 feet); head 

 long; baleen short, black to bluish in color; dorsal fin small 

 and curved; pectoral fin small; small, longitudinal furrows on 



Fig, 127. Sulphur-bottom Whale 



throat; body comparatively slender; "weight of whole animal, 

 by calculation, 147 tons" (taken from Scammon — a 95 foot 

 specimen); a 76 foot Whale from Newfoundland was said to 

 weigh 63 tons; spout tall and vertical; very active in habit, 

 swiftest of the Whales, speed when alarmed estimated at 12 

 miles per hour. 



Color. — Slaty gray to mottled bluish gray above; under- 

 parts varying from white to yellowish or grayish marked with 

 irregular white areas. 



Geographical Distribution. — Found on both Pacific and 

 Atlantic shores. 



Subfamily Megapterinae 



Genus Megaptera 



Humpback Whale. — Megaptera nodosa (Bonaterre) 



General Description. — A proportionally short and thick- 

 bodied Whale, reaching a maximum length of about 50 feet; 

 dorsal fin present as a low "hump"; pectoral fin very long 

 and narrow, knobbed along anterior margin ; flukes large, pos- 



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