28 



occurred during the first week in April, possibly a very critical time 

 in the creature's existence. But we really know very little of the 

 effect of local meteorological conditions upon the species ; and this 

 is a point that might very well be taken up by some of our stay-at- 

 home country members. 



In regard to its occurrence in the locality that I have just men- 

 tioned, I have repeatedly noticed a habit of the species that it may 

 be convenient to mention here The spot is a particularly sheltered 

 one, facmg almost due south, and consists of rough banks ijnd steep 

 down-lands more or less covered with natural herbage ; except at 

 one end where some few acres have been under cultivation for more 

 years than I can remember. This cultivated portion was last sown, 

 now some years ago, with lucerne, a crop that is particularly attrac- 

 tive to ('. ediisa. Yet during the whole of my experience, whether 

 C. edum has been abundant or comparatively scarce, and whether 

 the lucerne has been a full crop, or, as now, a few straggling plants 

 among the coarse herbage that is gradually overrunning the patch, 

 C. ednaa has always been proportionately far more common on the 

 rough uncultivated down-land than on that which was cropped with 

 the lucerne. In situation there is nothing to choose between the 

 two, and they are divided only by a rough track that for all practi- 

 cal purposes is no division at all. I cannot help thinking that the 

 insect is attracted to the rough uncultivated land as offering advan- 

 tages for carrying through its metamorphoses, which that which 

 has been under the plough does not. How often, too, in the lean 

 years, do we hear of its occurrence in the Isle of Wight, where the 

 broken ground to the west of Ventnor, untouched by cultivation, 

 appears to harbour it, as do also the rough sheltered nooks of the 

 southern coasts of Devon and Cornwall. It is from such places that 

 one more often than not gets the stray records in the years when 

 the species is not generally common in this country. 



Variation also must not be disregarded, but a very few woi'ds need 

 be said on the subject. In Britain we have one outstanding recur- 

 rent form of the female, viz., var. Iielice. Usually it is not relatively 

 very common, but in some seasons of great abundance it has been 

 noted in the estimated proportion of approximately one of the 

 variety to twenty of the type. In some of the more southern 

 countries of the insect's distribution this variety is said to occur 

 almost as frequently as the type. In the four cases that have come 

 under my notice, in which eggs obtained from var. /iclin' have been 

 reared to maturity, the proportion of the females bred have been five 

 /idicc to one edusa .- four helice to one ediisa : one helice to one cdiisa : 

 and fifty-two Jielice to nineteen editna = nea,r\y three to one respec- 

 tively ;■'■■' figures which appear to suggest that in years when the 

 variety has been unusually common in this country, the stock from 

 which they arose must have been of southern origin. Other than 



•■•■' " Ent. Bee," vol. xxvi., p. 49. " Proc," 1905, p. 75. 



