54 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



banded through the center with pure white, which suggests the lime 

 SO often seen in the excreta of birds. The entire creature is highly 

 glossed, which gives a fresh and moist appearance to the object, which 

 makes no attempt to conceal itself, depending entirely upon its 

 strangely camouflaged body for protection." (Insect behavior, p. 165, 

 1919.) ' 



Poulton summarizes the purpose of caterpillar adaptations as fol- 

 lows : "In the remarkable abundance and variety of methods by 

 which concealment is effected in Lepidopterous larvae, we probably 



see a result of their peculiarly defenceless condition Hence 



larvae are so colored as to avoid detection or to warn of some un- 

 pleasant attribute, the object in both cases being the same — to leave 

 the larva untouched, a touch being practically fatal." (The colours of 

 animals, p. 51, 1890.) 



On the concealment of lepidopterous pupae, the same author says : 

 " Protective Resemblance, either Special or General, is seen in nearly 

 all exposed pupae, but most chrysalides are buried in the earth or 

 protected by cocoons. The cocoons are often sufficient defense, 

 because the silk is very unpleasant in the mouth ; but such protection 

 only applies in the warmer weather when there is an abundance of 

 insect food. In the winter, insectivorous animals are pinched by 

 hunger, and would devour the pupa in spite of the cocoon. We there- 

 fore find that all cocoons which contain pupae during the winter are 

 well concealed, either spun between leaves which fall off and become 

 brown, or hidden under bark or moss, or constructed on the surface 

 of bark with a color and texture which renders them extremely diffi- 

 cult to detect." (Op. cit., pp. 51-52.) 



Pausing only long enough to note the incorrectness of the statement 

 " all cocoons which contain pupae during the winter are well con- 

 cealed " (witness those of Saturniidae, not to speak of the cases of 

 many Tineidae), we may pass to Howes' more imaginative account. 



We find, for instance, the chrysalis of a hutterfly, a species of Vanessa. It 

 hangs by a tiny silk-fastened stem nndcr a protecting fence rail. Within the 

 shell of the chrysalis, there is nothing but a mass of disintegrating tissues, a 

 thick fluid, studded with globules of fat. It is neither caterpillar nor butterfly. 

 It cannot thrash about from side to side or make a demonstration, there are no 

 spines to pierce a would-be enemy, no wings by which the creature might take 

 flight. It is as helpless now as so much custard, for the insect is in the process 

 of change from one form to another. 



^ This comment ignores the fact that a great many birds habitually devour 

 the excreta of their young, even returning to it when accidentally dropped, and 

 this nestling excreta is exactly of the luscious appearance described by Howes. 



