tributing to its numbers. It generally affects chalky and lime- 

 stone districts in this country, and makes its appearance the 

 beginning of June. 



From the large broods that have been observed of late 

 years in the vicinity of Langport in Somersetshire, it is to be 

 hoped that the caterpillar may be shortly met with, and I am 

 the more sanguine in my expectations from Mr. John Quekett, 

 a most zealous naturalist, residing in the neighbourhood. I am 

 indebted to him, as well as to Mr. Dale and Mr. D. Serrell, for 

 my series of specimens; and this gentleman tells me that he took 

 a considerable number lastyear in some woods, called the Holts, 

 near Stourton Caundle in Dorsetshire, in the month of July; 

 he principally found them in open places, amongst long grass 

 where stunted black-thorn bushes were growing: these woods 

 stand high, but are exceedingly wet in the winter. Mr. Mar- 

 shall also informed me some years since, that he once took 

 this moth in abundance in Kent, and it has also been found at 

 Darent and Tonbridge Wells. 



I have never met with it alive in England, but I captured a 

 male in descending the Puy de Dome in Auvergne; and Mons. 

 Duponchel says that in France it principally inhabits moun- 

 tainous districts, but he once took it plentifully in the woods 

 of Notre Dame, four leagues from Paris, by brushing the 

 heath. 



The similarit}' of S. dcalbata to some butterflies is very 

 striking: indeed the colour and shape of the wings and abdo- 

 men assimilate so well with the Papilionidae, that it seems only 

 to want the capitate antennae to complete its resemblance to 

 the Pontiae. 



It has been necessary to abandon the name of Idsea given 

 to this genus by Ochsenheimer, and employed in the 1st edi- 

 tion of the Guide, as it had been previously applied to a group 

 of Papilionidai; I have theretore adopted the more recent one 

 of Siona proposed by M. Duponchel. 



For specimens of the Plant, Pctroselimim (Sison Lirin.) sc- 

 getum. Corn Honewort, I am indebted to Dr. Bromfield, who 

 found them last October near Hyde, in the Isle of Wight. 



