Feb. 15, 1921 Leconte's Sawfly, an Enemy of Young Pines 745 



or rounded laterally and subapically but has a median apical concavity 

 and is ornamented with a transverse row of two pairs of spines. These 

 two pairs are slightly farther apart than are the two spines compos- 

 ing each pair. The epipharynx (PI. 90, E, I) is a thin skin, armed to each 

 side apically, or under each lobe of the labrum, with a series of inwardly 

 diminishing, opposed setae or blades, lacking symmetry, which often vary 

 somewhat in number and arrangement. The tentorial arms (PI. 90, 

 B, C) are a pair of supports or struts diverging to the widely separated 

 pair of adfrontal triangles from the tentorial bridge (PI. 90, B, C), which 

 is a thickened central attachment of the hypostoma. The hypopharynx 

 (Pi. 90, E, J), or floor of the mouth, rests between and beyond the paired 

 maxillary laciniae and is a thin membrane, minutely ornamented. Each 

 maxilla (Pi. 90, J-N) is composed of cardo, stipes, palpifer, 4-jointed 

 palpus, galea, andlacinia. The labium (PI. 90, J, K, O) is composed of 

 submentum (or mentum and submentum fused), mentum (or labial 

 stipes), ligula, and, to each side of the latter and attached basally to the 

 mentum (or labial stipes), a palpiger surmounted by 2-jointed palpus. 

 The mandibles (Pi. 90, H) are 5-toothed. 



Color. — The head capsule is orange-brown, excepting the spots sur- 

 rounding the eyes, which are black, and a part of the clypeus, which is 

 dark brown. The labrum is pale brown with its entire margin darkened, 

 the chitin of the maxillae and labium is brown to blackish, while the epi- 

 pharynx, hypopharynx, and ligula are pale white with their armatures 

 pale brown. 



THORAX 



Structural characters. — The prothorax (PI. 91, A) when examined 

 exteriorly and in its normal position appears to consist dorsally of but 

 two or three annulets, C and D always and B sometimes. This is due 

 to the constriction of the anterior circumference of the segment in its 

 connection with the head. An examination of the skin infoldings (PI. 

 91, D), however, will reveal all four of the primary divisions. On the 

 posterior margin of the segment, but caudad-ventrad of B, which is 

 always distinct supraspiracularly, there is a large, rather elongate area 

 in which the large thoracic spiracle is situated. Ventrad of B and an- 

 terior to this spiracular area is the preepipleurite ; below the preepipleu- 

 rite and the spiracular area is the postepipleurite ; and under the latter 

 comes the posthypopleurite, anterior to which, and rather strongly chiti- 

 nized, is the prehypopleurite. The prehypopleurite and posthypopleu- 

 rite support the 4-jointed legs. That part of the venter not occupied by 

 the prehypopleurite and posthypopleurite is divided by three transverse 

 folds into four annulations, the first annulation with a pair of latero- 

 ventral, chitinized areas, extending one from the base of each leg forward 

 to the occipital foramen, called neck plates. B supraspiracularly, C, pre- 

 epipleurite, postepipleurite, prehypopleurite, posthypopleurite, the leg 

 joints, and the second and third sternal folds are armed with spines. 



