1906] Animal Coloration. 155 



from successive cross-stripes, the spots arise, and these surface 

 arrangements of color appear to continue long after the internal 

 organs, the muscles, &c, have wholly altered their original 

 anatomical arrangement. Further, the successive series of spots 

 may unite later as longitudinal stripes, and such stripes we find in 

 the post-larval ling (Molva). We thus have a key to the arrange- 

 ment of color in a vast number of animals. Wild pigs, though 

 uniformly tinted when adult, exhibit when young a spotted skin, 

 says Mr. Alfred Tylor, and later become striped. The dark tapir 

 shows white spo*s, like the Virginian deer, when young. The 

 Canadian lynx is striped with dark reddish lines along its deep 

 brown body, as described in 1883 by Mr. Montague Chamberlain, 

 who henc^ deduced that it must be related to the Ocelot group of 

 the Felidae. Chickens, ducks, and other birds are similarly 

 striped, quite unlike their parents. No doubt the repeated spots, 

 bars and patterns, seen in caterpillars and many larval insects, are 

 really ancestral. Weissmann held that these stripes have come 

 down from a geological time when jointed reeds, and ribbed 

 grasses preponderated ; but this is apparently not a primitive 

 cause ; but like the zebra's and tiger's stripes they were ancestrally- 

 metameric and utility explains their persistence, and modification. 

 The striped tiger is practically invisible in his haunts among the 

 yellow sword-grasses of the jungle, while a troop of zebras on the 

 African plain, moving as they do in the moonlight, are practically 

 invisible, owing to their remarkable arrangement of colors. Many 

 young birds, like the gannet, may be of a dull brown color until 

 their third year, possibly a case of blurred spots or stripes, which 

 disappear and give place in the species named to a creamy white 

 plumage. The dark bars of the yellow perch (Perca) and of tropical 

 fishes like the Chaetodons. aid in obscuring these creatures 

 amongst aquatic weed-blades. On the other hand, spots of color 

 may be so modified as to resemble staring eyes, and may serve as 

 Poulton suggested, to direct the attention of enemies to non-vital 

 parts. The effect may, however, be the opposite and the eye-like 

 spots may so suddenly strike the attention of enemies and startle 

 them as to frighten them away.* The peacock butterfly ( Vanessa lo), 



* The eyelike spots on some larvae of Lepidoptera may have this effect, 

 e.g. the larva of the Elephant Hawk Moth (Chcerocampa elpenor.) 



