PHYTOMETEA MKEA. 135 



rounded, ribbed, and with flat under- side ; in colour 

 they were by that time a dull purplish-brown. On 

 August 5th the larvae began to emerge, little trans- 

 lucent almost colourless loopers to look at, but luckily 

 they did not all come out at once, otherwise I should 

 have had little to say about them ; I tried them with 

 every plant I could think of, but at first with no 

 success, and by far the greater part of them had died 

 of starvation, when luckily it came into my mind that 

 the very last specimen of the moth which I had cap- 

 tured myself was flying over or near some plants of 

 milkwort (Polygala vulgaris) ; a little bit of this plant, 

 therefore, was put in amongst the other twigs and 

 leaves, and in a short time, to my great delight, the 

 five surviving larvae had all found it out, and were 

 eating it very freely. They soon began to show an 

 increase in size, and turned pale green in colour, and 

 although looping very much, it was easy to see that 

 they had two pairs of ventral legs. I noticed that 

 whilst they were small their tint depended on the part 

 of the plant they ate, the blue flowers (I could find no 

 pink ones) causing them to appear of a dark bluish- 

 green. 



In the first week of September they attained their 

 full growth, and were then an inch long, slender if 

 compared with other Noctua larvae, but moderately 

 stout for loopers ; uniform in width when viewed from 

 above, but when seen sideways cylindrical in the 

 middle segments, and flatter towards the head and 

 tail ; the skin smooth ; the head round ; legs twelve, 

 the ventral pairs being on segments nine and ten, and 

 rudiments of another pair, too small for use, on the 

 eighth. 



The colour is a velvety full green, scarcely paler on 

 the belly ; the head mottled with faint brown ; a hasty 

 inspection would scarcely detect any lines, but on 

 looking closely the dorsal vessel appears as a darker 

 green thread, bordered with paler lines, between which 

 and the spiracles come three pale subdorsal lines ; the 



