THE ESSEX EMERALD. lOS 



The Essex Emerald {EucMoHs smaragdaria). 



In some examples of this species (Plate 43, Figs. 2, 3) the 

 green colour is brighter than in others, and very occasionally 

 it is tinged with bluish ; typically, there are white cross lines 

 on the fore wings, but the inner one is not infrequently absent, 

 and more rarely both are missing. The white central spot 

 is very rarely absent, and the edges of the fore wings are 

 yellowish. 



The caterpillar feeds on the sea wormwood {Artemisia 

 ma7'itima)^ and adorns itself with fragments of its food plant 

 in much the same manner as that of the species last referred 

 to. Although obtained in the autumn in some numbers from 

 its food plant, it seems to have been rarely met with in the 

 spring after hibernation. It is, therefore, advisable to collect 

 the caterpillars about September, and transfer them to plants of 

 the garden Artemisia abrotamnn^ locally known as " Southern- 

 wood," " Old man," or " Lad's love," or, where available, 

 wormwood {A. absinthiuin) will suit it admirably. Upon 

 either of these plants the larvae will hibernate, feed up in 

 the spring, and become full grown about May. The early 

 stages are figured on Plate 42, larva and pupa from photos by 

 Mr. H. Main. 



The moth is out in June and early July, but it is rarely seen 

 in the open, although over sixty years ago a few specimens 

 were put up from among grass and netted at St. Osyth ; in 

 later years an example or two have been taken at Sheerness in 

 Kent. Possibly, others may also have been captured in one or 

 other of the insect's haunts, but records are silent on the 

 matter. Barrett mentions a specimen emerging in September, 

 and the Rev. C. R. N. Burrows notes that part of a brood of 

 caterpillars reared from eggs, and fed on A. absinthium^ 

 attained the moth state during the autumn. So far as concerns 



