170 THE ZOOLOGIST. 



secretion of the Skunk is only emitted from the glands* when 

 the animal is attacked or irritated, an odour so powerful as above 

 desci'ibed cannot fail to have become to a great extent distributed 

 about its own pelage.t 



The odour of musk is frequently a purely sexual character in 

 animal life. Girard has always observed that the musky odour 

 which is emitted by two species of Sphinx moths is peculiar to 

 the males, t During the season of love a musky odour is emitted 

 by the submaxillary glands of the Crocodile, and pervades their 

 haunts. § Dr. Junker found that the deck of the steamer on 

 which he travelled up the Blue Nile was for some days pervaded 

 by a musky odour after a wounded Crocodile had been despatched 

 thereon. || According to Mr. Ramsay, writing on the Australian 

 Musk-Duck (Biziura lobata), the smell which the male emits 

 during the summer months is confined to that sex, and in some 

 individuals is retained throughout the year ; he had never, even 

 in the breeding season, shot a female which had any smell of 

 musk. IF In the Australian Echidna, " during the rut, both sexes 

 produce a most conspicuous odour, which is probably destined 



Nat.' p. 200). — On this point, Darwin, who seems to have anticipated most 

 suggestions and objections bearing on his theory, must be quoted: " Natural 

 Selection cannot possibly produce any modification in a species exclusively 

 for the good of another species, though throughout nature one species in- 

 cessantly takes advantage of, and profits by, the structures of others " 

 (' Origin of Species,' 6th edit. p. 162). 



* The glands lie on either side of the rectum, and are imbedded in a dense 

 gizzard-like mass of muscle, which serves to compress them so forcibly that 

 the contained fluid may be ejected to the distance of four or five metres 

 (approximately 13 to 16J feet). Each sac is furnished with a single duct that 

 leads into a prominent nipple-like papilla that is capable of being protruded 

 from the anus, and by means of which the direction of the jet is governed 

 (Merriam, ' Mam. Adirondack Reg. T. L.S. N. Y.' i. p. 76, 1882). 



f According to Mr. Hudson, the Common Deer of the Pampas {Cervtts 

 campestris) gives out — in the male — an effluvium quite as far-reaching, 

 although not so abominable in character as that of the Mephitis ? . . . Yet 

 it is not a protection — on the contrary, the reverse, . . . and wherever 

 Pumas are found, Deer are never very abundant. The Guachos, however, 

 say it is protective against snakes (' The Nat. in La Plata,' pp. 159-60). 



J ' Zool. Eec' 1869, p. 347. 



§ Owen, ' Anatomy of Vertebrates,' vol. i. p. 615 (1866). 



|| ' Travels in Africa,' 1875-8, Eng. edit. p. 203. 



IT « Ibis,' n.s. vol. iii. p. 414 (1867). 



