RORQUALS 153 



way summed up the specific characters of these four 

 northern whales we say northern, though, as will be 

 pointed out, it is probable that the southern forms are 

 really of the same species. 



Bahznoptera sibbaldii, Gray* ( = B- latirostris, 

 Flower, and has probably other synonyms), has a 

 length of 70-85 feet. Robust in form (for a 

 Rorqual), proportions of height and length being 

 as i : 5^. Colour dark bluish grey. Dorsal fin at 

 commencement of last quarter of body. Vent 

 situated in front of vertical line from anterior margin 

 of dorsal fin. Pectoral fins large, \ of total length of 

 body. Baleen and bristles black. Number of plates 

 up to 400 ; their length 930 mm. 



This, the greatest of whales, and indeed of all 

 animals living or extinct, f is named in honour of Sir 

 Robert Sibbald, author of the Phalainologia nova and 

 inventor (?) of the " High-finned Cachalot." 



It is to be distinguished from other Rorquals j by 

 its superior size, and by the various other characters 

 given in the above description of its essential features. 

 The whalers know it by its large size and by the 

 height to which it spouts. Its speed too, when going 

 rapidly, is great. Something like twelve miles an 

 hour are accomplished by a Balcenoptera sibbaldii 

 when putting its best foot foremost. It is a species 



fr Proc. Zool. Soc., 1847, p. 92. Sir W. Turner has described the 

 anatomy. (Trans. Roy. Sec., Edinb., 1872.) 



t Unless the recently-described 130-foot Dinosaur turns out to have 

 been accurately measured. 



I It obviously comes closest to B. musculus. 



