1892., 123 



to plant, in whicli case eggs from one moth might extend over a con- 

 siderable area. The wonder, then, is that its habitat should be so 

 exceedingly restricted, as it appears to be, on the Norfolk coast (see 

 Ent. Mo. Mag., xxv, pp. 258 and 398). 



The egg is of fair size, oblong-oval, bright glistening orange-yellow. Those first 

 deposited, about June 17th, hatched out in numbers on the 2yth and 30th, and by 

 July 4th all of them seemed to be out ; the minute newly emerged larvae were 

 yellow, tinged with green. By July 14th, they were nearly a quarter of an inch 

 long, pale yellow or greenish, and having faint indications of darker dorsal and sub- 

 dorsal lines. A fortnight later, on the 28th, many of them had attained to 

 five-eighths of an inch, were slender, and tapered a little towards the head. Colour 

 now bright green, a little freckled with white dots, the sub-dorsal and spiracular stripes 

 clear white, but as yet with no indication of the pink colouring on the spiracular 

 region, which was so noticeable in the parent larvae ; head bright green, the man- 

 dibles, and also the tips of the anterior legs, pale brown. 



Prior to this time, the growing plant of Arte^n. maritima had been 

 eaten away, and it being inconvenient to have to send to Norfolk for 

 a fresh supply every time it was wanted (as I had done the previous 

 autumn), I tried the larvae with Artem. vulgaris, and the garden 

 " Southernwood," Artem. ahrotanum. Of the former they ate very 

 little, but I was pleased to find that they took to the latter with 

 evident relish, and I have never since had any anxiety as to their food 

 supply, having fed them exclusively on this plant. 



On August 9th, the largest larvae were nearly an inch and a quarter long, and 

 apparently full-grown; and by the 20th they were spinning up rapidly. They were 

 proportionately rather stouter, but the only variation in colour, from the descrip- 

 tion made of July 28th, was in the sub-dorsal lines, which were not so white, being 

 formed apparently of a white powdering, through which the green distinctly asserted 

 itself; the spiracular stripes were still intensely white, as was also a ventral central 

 stripe. What surprised me very much was, that in the over four hundred larvae I 

 reared in 1890, not a single one showed the least trace of the pink marking so pretty 

 and conspicuous in many of the captured larvae of 1889 ; nor did it re-appear at all 

 in any of the larvae of the succeeding generation I reared last year. The pink colour 

 was of exactly the same tint, and evidently appeared simultaneously with the flower 

 buds of the Artemisia maritima, and is doubtless a good example of protective 

 assimilation ; whereas, the Artemisia abrotanum being always green (I have never 

 seen it flower at all in Yorkshire), the appearance of the pink on the larvae would 

 have been not only useless, but disadvantageous. But that the larvae should entirely 

 lose every trace of it, the very first season of their altered environment, was to me 

 most extraordinary. 



One of Mr. Barrett's observations, that the larva has an occasional 

 habit of "standing, apparently, upon its head" (Ent. Mo. Mag., xxv, 

 p. 258), I am not able to confirm. This statement seemed to me so 

 remarkable, that I spent hours, during all parts of the day, and well 



