42 EUPITHECIA EXTENSARIA. 



green, the mandibles and also the tips of the anterior 

 legs pale brown. 



Prior to this time the growing plant of Artemisia 

 maritima had been eaten away, and it being incon- 

 venient 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 larva? with Artemisia vulgaris, 

 and with the garden " southernwood," Artemisia abro- 

 tanum. 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 the 9th of August 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 description made on 

 the 28th Julv was in the subdorsal lines, which were 

 not so white, being formed apparently of a white 

 powdering, through which the green distinctly as- 

 serted 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 larva? 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 larva? of 

 1889, nor did it reappear at all in any of the larva? 

 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 larva? would have been not only useless, 

 but disadvantageous. But that the larva? should 

 entirely lose every trace of it the very first season of 



