VIII ORIGIN AND USES OF COLOUR IN ANIMALS 211 



concealment, but as a direct means of securing their prey by 

 attracting them within the enemy's reach. Only a few cases 

 of this kind of coloration have yet been observed, chiefly 

 among spiders and mantidne ; but, no doubt, if attention 

 were given to the subject in tropical countries, many more 

 would be discovered. Mr. H. 0. Forbes has described a 

 most interesting example of this kind of simulation in 

 Java. While pursuing a large butterfly through the jungle, 

 he was stopped by a dense bush, on a leaf of which he 

 observed one of the skipper butterflies sitting on a bird's 

 dropping. "I had often," he says, "observed small Blues 

 at rest on similar spots on the ground, and have wondered 

 what such a refined and beautiful family as the Lycaenidae 

 could find to enjoy, in food apparently so incongruous 

 for a butterfly. I approached with gentle steps, but 

 ready net, to see if possible how the present species was 

 engaged. It j^ermitted me to get quite close, and even to 

 seize it between my fingers ; to my surprise, however, part of 

 the body remained behind, adhering as I thought to the 

 excreta. I looked closely, and finally touched ivith my finger 

 the excreta to find if it were glutinous. To my delighted 

 astonishment I found that my eyes had been most perfectly 

 deceived, and that what seemed to be the excreta was a 

 most artfully coloured spider, lying on its back with its feet 

 crossed over and closely adpressed to the body." Mr. Forbes 

 then goes on to describe the exact appearance of such excreta, 

 and how the various parts of the spider are coloured to 

 produce the imitation, 'even to the liquid portion which 

 usually runs a little down the leaf. This is exactly imitated 

 by a portion of the thin web Avhich the sj^ider first S23ins 

 to secure himself firmly to the leaf ; thus producing, as Mr. 

 Forbes remarks, a living bait for butterflies and other insects 

 so artfully contrived as to deceive a pair of human eyes, even 

 when intently examining it.^ 



A native species of spider (Thomisus citreus) exhibits a 

 somewhat similar alluring protection by its close resemblance 

 to buds of the wayfaring tree, Viburnum lantana. It is pure 

 creamy-white, the abdomen exactly resembling in shape and 

 colour the unopened buds of the flowers among which it takes 

 ^ A XaturaList' s Wanderings in the Eastern Archijjelago, p. 63. 



