oc. 



October, 1920. The Irish Nalnralist. ' 93 



THE HOODED OR BLADDER-NOSED SEAL, 

 CYSTOPHORA CRISTATA (ERXL.). 



BY R. F. SCHARFF. 



This seal seems to be more or less confined to the colder 

 regions of the North Atlantic and is met with in numbers 

 off the coasts of Greenland, Iceland, and Spitsbergen. The 

 young and females of this species do not differ to any marked 

 extent from other seals externally. Their chief character 

 of distinction lies in the teeth, for the cutting or incisor 

 teeth are reduced to two pairs in the upper and a single 

 pair in the lower jaw. The male develops a striking external 

 feature on reaching adolescence. Above the nose is formed 

 a large inflatable sac or hood which can be dilated, giving 

 the animal the appearance of having a big swelled head. 

 For what purpose the male seal possesses this appendage is 

 not known, and it is believed that the sac is only dilated 

 when the animal is excited or irritated. In that state it 

 must present a very remarkable and rather formidable 

 appearance, and being naturally of a fierce disposition the 

 animal is likely to spread terror among its enemies. A 

 mounted specimen of this Hooded Seal from Greenland has 

 recently been added to the collections of the National 

 Museum. 



The special interest this, seal presents to the Irish 

 naturalist is that it occasionally seems to wander southward 

 from its northern home as far as the coasts of the British 

 Islands and even France. Dr. Trouessart's statement that 

 only the young migrate southward is probabl}- incorrect. 

 For Mr. Southwell, quoting from some ancient chronicler, 

 informs us that fishes resembling the body of a man with 

 cowls on their heads like monks were long ago noticed in 

 the Firth of Forth. No doubt this account refers to the 

 male of the Hooded Seal. We also have reports of Hooded 

 Seals having been seen on the coast of the Orkney Islands. 

 Several young specimens have actually been taken on the 

 coasts of, England and France. 



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