THE "WOOD WASP" AND AUTUMN INSECTS 493 



is rough and of a green colour, sprinkled 

 with minute yellow spots. Seven obhque 

 yeUow stripes appear on each side of the 

 body, which fade into the general green 

 colour on the back, as seen in the example 

 on the right of the illustration ; the horn 

 at the tail is of a yellow colour shaded with 

 brown. 



This caterpillar may be easily mistaken 

 for that of the Lime Hawk-Moth (which 

 moth was illustrated on page 72). as their 

 colours are very much alike. The larva 

 of the Lime Hawk- Moth, however, has 

 the obhque ^-ellow 

 stripes tinged with 

 pink or purple, and 

 the horn at the tail 

 is blue above and 

 yellow beneath ; 

 also, when full 

 grown, its body is 

 more slim than that 

 of the Poplar Hawk- 

 Moth. Then there is 

 the Privet Hawk- 

 Moth (illustrated on 

 page 213), the larva 

 of which is very 

 similar in shape to 

 both the foregoing, 

 but much larger — 

 sometimes three 

 inches in length — 

 and its body is 

 smooth, while the 

 obhque stripes are 

 whit e, edged in 

 front with purple, 

 and the tail horn is 

 black above and 

 yellow below. 



It will be seen, 

 therefore, that the 

 larvae of the famihar 

 Hawk- Moths bear 

 some general resem- 

 blance to each other; 

 there are other simi- 

 lar species that may 

 occasionally be met 

 with, but their general shape, striking 

 colours, and the horn at the tail serve to 

 distinguish them as Hawk-Moth larvae. 



Perhaps I had better add that the tail 

 of these larv<e need not be feared. What 

 function that organ serves is a matter 



63 



upon which naturalists have not yet 

 decided. Nevertheless, an unfamiliar 

 animal, possessing at its tail a horn that 

 looks as if it could sting, always commands 

 respect. Besides, when these caterpillars 

 are resting amongst the leaves after feeding 

 if one is disturbed it immediately begins 

 to wave its head from side to side in an 

 angry fashion that plainly shows its 

 annoyance, and at the same time gives 

 the impression that it really intends to 

 protect itself if touched again. This 

 threatening attitude, combined with a 



CATERPILLARS OF THE POPLAR HAWK-MOTH. 



tail that seems to bear a stinging weapon, 

 probably deters its assailants from further 

 attacks ; indeed, I have seen many 

 human assailants vcr\- much alarmed by 

 the mo\-ements of these caterpillars ; 

 nevertheless, their defence is simply bluff, 



