946 MR. R. I. POCOCK ON WARNING COLORATION [DeC. 1 5, 



glands and stings which make them dangerous to meddle with. 

 They also as a very general rule have no need of procryptic color- 

 ation to enable them to capture wary or keen-sensed prey. Their 

 movements are usually slow and deliberate, and instead of avoiding 

 they seem rather to court observation, some indeed attracting 

 attention by the emission of characteristic sounds. Verj com- 

 monly also they are hard, tough, and difficult to kill. 



Porcupines of the genus Hystrix furnish a good instance of 

 this. Protected by their spine-armature, they are quite con- 

 spicuous in the dusk by reason of the predominance of white on 

 the dorsal surface, and they make themselves heard by shaking 

 their caudal rattles and uttering hoarse grunts. This I pointed 

 out last year (see P. Z. S. 1906, p. 902, pubd. April 1907). Sub- 

 sequently I noticed that the Canadian Tree-Porcupine {Eriihizon), 

 which which has no rattle, but is conspicuously coloured when 

 its spines are erected, possesses a strong and unpleasant odour 

 recalling that of concentrated human perspii'ation. This is also 

 vei V possibly one of the aposematic attributes of the species ; and 

 I have recently come across a passage showing that exactly the 

 same discovery was made about foity yeais ago by that keen 

 naturalist Charles Kingsley in connection with the Brazilian Tree- 

 Porcupine or Coendoo [Coendu). He wrote : " More than once we 

 became aware of a keen and dreadful scent, as of a concentrated 

 essence of unwashed tropic humanity, which proceeded fiom that 

 strange animal, the Porcupine with a prehensile tail, who prowls 

 in the tree-tops all night, and sleeps in them all day, spending 

 his idle hours in making this hideous smell. Probably he 

 or his ancestors have found it pay as a protection ; for no 

 Jaguar or Tiger-cat, it is to be presumed, would care to meddle 

 with any thing so exquisitely nasty, especially when it is all over 

 sharp prickles." * Tt is interesting that the same comparison 

 should have been independently employed both by Kingsley and 

 myself in attempting to describe the scent of these Porcupines ; 

 and that he should have anticipated me by so many years in 

 assigning a protective value to it. 



Up to the present time the only Mammals, apart from Porcu- 

 pines, claimed to be warningly coloured, so far as I am aware, are 

 the Skunks of America (Jlejyhitis, Cove/xdus, SpUogale) and the 

 Zorillas of Africa belonging to the genus Ictonyx and known in 

 Cape Colony as Cape Polecats. These are black Mustelines orna- 

 mented dorsally, as a rule, with broad clear white longitudinal 

 stripes, which sometimes coalesce or almost coalesce to form a 

 continuous white field. When attacked they increase their 

 apparent size and enhance their conspicuousness by erecting the 

 long hairs of their bodies and by brandishing their bushy white 

 tails. At the same time they eject from their anal glands a 

 volatile fluid, with a most repulsive, acrid and persistent odour. 

 Skunks in captivity are frequently quiet undemonstrative animals ; 



* ' At Last,' p. 248, cd. 3, 1905 ; quoted also by J. G. Weed in Waterton's 

 ■Wanderings in South America,' p. 458, MacMillan & Co., 1879. 



