THE TRUE SEALS. 



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black eyes in an apparently meaningless stare." 

 Dr. R. Brown on the Seals of Greenland in the 

 Manual of Instructions for the Arctic Expedition, 

 edited by Rupert Jones, 1875. 



The southern seas, including the Mediter- 



ranean, are inhabited by seals which have 

 two incisors in each half of the jaw both 

 above and below, small canines, and molars 

 with pointed lateral cusps besides the sharp 

 middle one. Of these teeth the first has 



Fig. 129. The Sea-leopard (Lepfoiiy.v leopardinus). 



only one root, while the others have two. 

 These seals form the genus Leptonyx 

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Dental formula: 



= 32 teeth. 



As representative of this genus, which in- 

 cludes also the Monk-seal of the Mediter- 

 ranean {Leptonyx monachus (Monaclms albi- 

 venter) ), an illustration is given of the sea- 

 leopard {Leptonyx leopardinus), fig 129, of 

 the Antarctic Seas, which attains the length 

 of about 12 feet, and has a gray-brown fur 

 interspersed in places with bright yellow 

 spots. The nails are small but sharp, their 

 colour black. On the hind-flippers they dis- 

 appear with age. The skull is longish, the 

 fur short, thick, without down. 



The true seals, in the most restricted sense 



of that term, the animals forming the genus 

 Phoca, have three incisors above, like the 

 land Carnivora, but only two below. Dental 



formula: ; = 34 teeth. 



The molars are deeply notched and very 

 sharp. A somewhat different genus (Halichce- 

 rus) has conical molars without lateral lobes. 



As representative of this group composed 

 of the ordinary seals of our coasts, found only 

 in the northern hemisphere, the group to 

 which among others the Common Seal or 

 Sea-calf (Phoca vitulina of Linnaeus) belongs, 

 the Greenland Seal (Phoca grcenlanchca), fig. 

 130, has been selected for illustration. It is 

 the commonest species in the northern seas, 

 and its pursuit is carried on chiefly by the 



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