iii((rhin<is (1)1(1 attitudes of lepi(hi])t('rniis hirice. 307 



those of S. tridiidrd are green underneath, as in *S'. rubra. 

 My own observations being very strongly in favour of 

 the protective vahie of the coloration in this S2)ecies, 

 and Mr. Meldola apparently believing the same thing, I 

 had fallen into the error of supposing that his instances 

 agreed with my own. Furthermore, all the larvae I 

 had found upon S. viminalis had been white-green, and 

 those upon sallows {S. rubra) with green under sides, 

 like S. triandra, had been yellow-green ; so that my 

 observations were the exact reverse of those quoted b}'- 

 Mr. Meldola. But even without observations upon the 

 particular species {S. viminalis) I should have doubted 

 whether the instances alluded to were entirely normal, 

 and expressed the real phytophagic tendency of the two 

 plants. Such doubts would follow from the general con- 

 clusions arrived at concerning the effect of leaves, 

 with certain colours and surfaces. The same opposition 

 in experience is also indicated by Mr. Meldola when he 

 speaks of six larvae being found upon a species of sallow, 

 four of them being bright green and two bluish green. 

 Nevertheless, my experiments rather supported Mr. 

 Meldola's instances than my own view, for the S. riminalis 

 larvae were not nearly so whitish as those fed upon 

 apple. I am hoping to experiment upon the effect of 

 this food-plant and of S. triandra, on a large scale 

 during the present summer (1886). 



(2) >S. ligustri. — Mr. Meldola quotes two instances of 

 phytophagic coloration in this larva. In one case the 

 larvae feeding on lauristinus were darker than those upon 

 privet ; in the otlier instance ash produced a more 

 greyish green than either lilac or privet. I have noticed 

 the same thing with regard to larvae found upon ash, but I 

 should say that these larvae resembled the lilac forms, and 

 differed from the privet. Mr. W. Davis's expression 

 "greyish green," quoted by Mr. Meldola, applies extremely 

 well to the larvae which I have found upon lilac. It is 

 now many years since I have observed this difi'erence (at 

 Reading, Oxford, and this year at Great Malvern) 

 between the adult larvae found upon privet and lilac. 

 The difference is very hard to define, but very real. 

 The green ground colour and the purple stripes are 

 duller in the lilac larvae, and the difference is independent 

 of the lightness or darkness of the larvae, for light and 

 dark individuals occur in both varieties. This year I 

 reared twenty-four larvae from the egg, in two separate 



