THE BRITISH PTEROPHORI. 51 



fellow. I would suggest collecting sprigs of the plant from places 

 where the insect is known to occur ; where thyme grows plenti- 

 fully, a good bundle might be gathered in May, from which 

 P. tetradactylus as well as the above would possibly be 

 obtained. 



P. spilodactylus occurs freely amongst its food-plant, Marm&i«??i 

 vulgare, on downs at Freshwater, in the Isle of Wight. The plant 

 used to be common on the downs near Ventnor, but is of rare 

 occurrence there now. In several cottage gardens in the island 

 where the wild herb has been transplanted, the insect is to be 

 obtained. The larvse and pupae may both be found by day on the 

 upper sides of the leaf, often a large number on a plant. Mar- 

 rah'mni, I believe, is not often found wild in other parts of 

 England, but where known to grow wild or cultivated this plume 

 should be looked for. 



Fleabane [Inula) in marshes and other damp places should 

 produce P. Uthodactylus. The imago may be started from herb- 

 age in the daytime, but it is such a sluggish insect that nothing 

 short of actual dislodgment will cause it to get on the wing ; even 

 this unwonted energy ceases when it has flown a few yards. Just 

 after dark it becomes a little more lively, and flutters about over 

 the larval pabulum, which I always find to be Inula dysenterica. 

 "When the leaves of this plant are observed to have a whitened 

 appearance, due to the fleshy part being eaten away, the larvae 

 may be found if looked for just after dark. They come from 

 their hiding-places at this time. I could never find them in the 

 day, although I knew that they were close at hand, from the 

 evidences of their recent feeding. Young larvae are to be found 

 in the primary shoots; and it has just occurred to me that 

 possibly when the leaves are fully expanded, they may enter the 

 stem to hide during the daytime. I have frequently pulled up 

 plants, shook them, examined the ground, stones, &c., but never 

 thought to split the stems. 



Pterophorus isodactylus and P. microdactylus are also to be 

 found in marshes ; the former amongst Senecio aquaticus, in stems 

 of which the larva feeds. Probably it may affect other plants of 

 the tribe of ragworts. The last-named plume occurs among and 

 near Eupatorium cannabinum, the food-plant of the larva, which 

 also feeds in stems. 



In salt marshes Agdistes Bennetii may be found ; the larva 



