JL] GHJ&ROCAMPA ELPENOR. 53; 



again find species for instance, Lophyrus soda which 

 live on the pine, and in which the same style of 

 colouring is repeated. 



Let us now take a single group, and see how far we 

 can explain its various colours and markings, and what 

 arc the lessons which they teach us. For this purpose, I 

 think I cannot do better than select the larvee of the 

 Sphingidce, which have just been the subject of a mas- 

 terly monograph by Dr. Weismann, from whom most 

 of the following facts are taken. 



The caterpillars of this group are very different in 

 colour green, white, yellow, brown, sometimes even 

 gaudy, varied with spots, patches, streaks, and lines. 

 Now, are these differences merely casual and accidental, 

 or have they a meaning and a purpose ? In many, 

 perhaps in most cases, the markings serve for the 

 purpose of concealment. When, indeed, we see cater- 

 pillars represented on a white sheet of paper, or if we 

 put them on a plain table, and focus the eye on them, 

 the colours and markings would seem, if possible, to 

 render them even more conspicuous ; as, for instance, in 

 Deilephila galii; but amongst the intricate lines and 

 varied colours of foliage and flowers, and if the insect be 

 a little out of focus, the effect is very different. 



Let us begin with the Charocampa elpenor, the 

 elephant hawk-moth. The caterpillars, as represented 

 in most entomological works, .are of two varieties, most 

 of them brown (Fig. 46), but some green. Both have 

 a white line on the three first segments ; two remarkable 

 eye-like spots on the fourth and fifth, and a very faint 

 median line ; and are rather more than four inches long. 

 I will direct your attention specially, for the moment, to 



