Chap. XVIII.] ODORS. EMITTED. 265 



of the male consists of a wild, hoarse, gurgling noise, 

 which is audible at a great distance, and is believed to be 

 strengthened by the proboscis. Lesson compares the 

 erection of the proboscis to the swelling of the wattles of 

 male gallinaceous birds while they court the females. In 

 another allied kind of seal, namely, the bladder-nose 

 {^Gystophora cristata), the head is covered by a great 

 hood or bladder. This is internally supported by the sep- 

 tum of the nose, which is produced far backward and rises 

 into a crest seven inches in height. The hood is clothed 

 with short hair, and is muscular ; it can be inflated until 

 it more than equals the whole head in size ! The males 

 when rutting fight furiously on the ice, and their roaring 

 " is said to be sometimes so loud as to be heard four miles 

 off"." When attacked by man they likewise roar or bel- 

 low ; and whenever irritated the bladder is inflated. 

 Some naturalists believe that the voice is thus strength- 

 ened, but various other uses have been assigned to this 

 extraordinary structure. Mr. R. Brown thinks that it 

 serves as a protection against accidents of all kinds. This 

 latter view is not probable, if what the sealers have long 

 maintained is correct, namely, that the hood or bladder is 

 very poorly developed in the females and in the males 

 while young. * 



Odor. — With some animals, as with the notorious 

 skunk of America, the overwhelming odor which they 

 emit appears to serve exclusively as a means of defence. 

 With shrew-mice (Sorex) both sexes j)ossess abdominal 



^ On the sea-elephant, see an article by Lesson, in ' Diet. Class. Hist. 

 Nat.' torn. xiii. p. 418. For the Cystophora or Stemmatopus, see Dr. 

 Dekay, 'Annals of Lyceum of Nat. Hist. New York,' vol. i. 1824, p. 94. 

 Pennant has also collected information from the sealers on this animal. 

 The fullest account is given by Mr. Brown, who doubts about the rudi- 

 mentary condition of the bladder in the female, in ' Proc. Zoolog. Soc' 

 1868, p. 435. 



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