114 ANIMAL COLOEATIOX. 



too, appears to select a snowy patcli of gTonnd to rest upon, 

 in preference to rocks and stones which are not covered, with 

 snow; so at least says Bishop Stanley, in his "History of British 

 Birds" (p. 149) of a pair of these birds shot in the severe 

 winter of 1823, in Northnmberland. These birds had, we are 

 told, " been noticed in the wild and rocky parts of an open 

 moor, either perched upon the snow, or on some large solitary 

 stone projecting from it, from whence, without attracting 

 notice by any contrasting colour, they could look out for their 

 prey." 



Indifferent Colours. 

 There are numerous examples of coloration the reverse of 

 protective, which nevertheless cannot be regarded as "warning," 

 inasmuch as they are not accompanied by disagreeable qualities. 

 The most prominent instances are animals which are entirely 

 white or largely marked by white. Mr. Wallace has pointed 

 out that the defenceless inhabitants of islands* often show 

 such conspicuous colours ; the butterflies of some of the 

 islands of the Eastern Archipelago have more white upon their 

 wings than their relations upon the mainland ; this he 

 attributes very ingeniously to the smaller need for protection 

 owing to the less numerous insectivorous animals. The 

 struggle for existence is, in this particular, less keen ; hence the 

 elimination of unfavourable varieties proceeds with diminished 

 severity. Among British Lepidoptera there are a number of 

 white species — butterflies as well as moths. As to the butter- 

 flies — the Cabbage White and its allies — it may reasonably be 

 urged that they have not so great a need for iirotectiou as 

 many other insects : as a rule, butterflies do not appear to be so 

 favourite an article of food with birds and lizards, as do moths : 



* Sir Walter Buller has remarked upon the abundance of albinos- 

 among New Zealand birds. 



