64 NEMATUS RUFICORNIS. 



being darker, and there is no fuscous cloud in the 

 middle of the wing; the posterior tarsi are black 

 entirely, and the antennas if anything are longer and 

 taper apparently more towards the apex. I doubt, 

 however, if these characters will be sufficient to enable 

 the two species to be separated. 



From appendiculatus it differs in the longer tarsi 

 and shorter calcaria, thicker antennas ; and the colora- 

 tion of the stigma and legs is different ; the third 

 cubital cellule being also smaller. Puncticeps agrees 

 with it very closely, and I think that it will prove to 

 be a variety of ruficornis, varying from it merely in 

 having the antennae, labrum, coxae, trochanters, and 

 femora black, and, as we have seen, ruficornis shows 

 considerable variation in the colour of these parts. 

 Thomson, however, states that the antennas in punc- 

 ticeps are thinner than in ruficornis. 



The larva feeds on willows (Salix viminalis, vitellina, 

 &c ) and birch in July, and there is a second brood 

 during the autumn. It is green, the body long ; the 

 head is paler than the body and has a line on each side 

 touching the eyes, but not uniting on the top, and 

 another goes down the centre of the face; mouth 

 brownish. There are two blackish marks over the 

 thoracic legs, and another small one in front of the 

 first pair. When full fed it becomes of a yellowish- 

 green colour. The cocoon is spun in the earth, the 

 pupa being green. The larvae eat along the edge of the 

 leaf. 



From this description it is seen that the larva 

 agrees very closely with that of appendiculatus. I have 

 also seen specimens with the head dotted over with 

 fuscous. 



Perilissus filicornis, Gr., preys on it. 



Ruficornis is one of our commonest saw-flies, and is 

 met with in all districts, the imagos appearing early in 

 June. It occurs in Lapland, Scandinavia, Germany, 

 Holland, France, Switzerland, Austria and Eussia. 



