ZOOLOGY. — DELPHI'NUS DEDUCTOR. 497 



This animal grows to the length of about 24 

 feet; the average length of the adults maybe about 

 20, and their greatest circumference 10 or 11 feet. 

 The measurements of one examined by JMr Wat- 

 son, were as follow. Length 19^ feet ; greatest cir- 

 cumference 10 ; pectoral fin (the external portion) 

 3 1 feet long, by 18 inches broad ; dorsal fin 15 in- 

 ches high, by 2 feet 3 inches broad ; breadth of the 

 tail 5 feet. Another individual was 21^ feet in 

 length; and a third 20 feet in length, and 11^ in 

 circumference. 



The skin is smooth, resembling oiled silk; the 

 colour is a deep bluish-black on the back, and gene- 

 rally whitish on the belly ; the blubber is 3 or 4 in- 

 ches thick. The head is short and round ; the up- 

 per-jaw projects a little over the lower. Externally 

 it has a single spiracle. The full grown have gene- 

 rally 22 to 24 teeth, fths to l^th inches in length, in 

 each jaw. Mr Watson observed one with 28 teeth 

 in the upper-jaw, and 24 in the lower. In the aged 

 animals some of the teeth are deficient ; and in the 

 sucklings none are visible. When the mouth is 

 shut, the teeth lock between one anotlier, like the 

 teeth of a trap. The tail is about 5 feet broad ; 

 the dorsal fin about 15 inches high, cartilaginous 

 and immoveable *. 



This kind of dolphin sometimes appears in large 

 herds off the Orkney, Shetland, and Fcroe Islands. 



* Dr TrailLj MS. paper. 

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