ORDER HYMENOPTERA 213 



sule is in alignment with the long axis of the body until 

 the sixth stage; but they are tissue feeders from the begin- 

 ning. In many the thorax is wider and thicker than the 

 abdomen, especially so when young. 



The depressed, somewhat triangular head-capsules are 

 nearly twice as broad as long. The mouthparts project in 

 front. There is never more than a single ocellus on either 

 side of the head. This will distinguish them from most 

 lepidopterous miners. In these, as in lepidopterous miners 

 there is a tendency for the front to extend farther towards 

 the vertex than in free-feeders. In Scolioneura the stem of 

 the epicranial suture is only about one-half the length of 

 the arms and the caudal end of the front is an acute angle. 

 In sawfly larvae there are no sclerites corresponding to the 

 adfrontal plate of caterpillars. 



Thoracic legs are present and are from one to five jointed. 

 Their position is far to the side and between them in line 

 with the abdominal prolegs secondary protuberances are 

 sometimes developed. In most miners the thoracic legs 

 are not much used, but Metallus rubi continues to make 

 some use of them. Abdominal prolegs are present on seg- 

 ments 2, 3, 4, 5, 6, 7 and 8 of the abdomen. Profenusa 

 collaris is represented to have slight protuberances on the 

 1st and 9th segments also. Anal prolegs are present in 

 some miners, lacking in others. When present they may 

 be separate, or fused to a conical stump and perhaps ringed 

 around at the base with chitin. In no sawflies are hooks 

 (crotchets) developed on the prolegs and in the miners, 

 especially in the early instars, prolegs are much less promi- 

 nent than in the free-feeders. 



In color the mining sawflies are greenish white or pale 

 green, the color being largely due to ingested parenchyma. 

 The head capsule is usually brownish; honey-brown or 

 darker. The prothoracic shield is always present and may 

 be dark in color. Sometimes the second thoracic segment 



