401] LARVAE OF THE TENTHREDINOIDEA—YUASA 83 



Streak caudad and dorsad of each ocellara; antennae four-segmented, 

 subconical or sublimpet-shaped, sometimes in part fused; segment 1 

 minute, segments 2 and 3 reduced to mere line on cephalic aspect, segment 

 4 minute, subconical; mouth-parts and cervical sclerites fuscous to black- 

 ish; maxillary palpi with two distal segments distinctly smaller than 

 segment 2, which is sometimes longer than all the other segments taken 

 together; galea larger than labial palpus; sericos distinct, circular; sub- 

 spiracular and surpedal lobes with a few microscopic setae; glandubae 

 probably microscopic, usually obsolete; spiracles usually winged; cuticle 

 microscopically spinulate; free leaf-feeders. 



SPECIES OF NEMATUS 



1(4) Vertex with a fuscous streak caudad and dorsad of each ocellara; maxillary palpi 

 with segment 2 shorter than all the other segments taken together 2. 



2(3) Vertex with fuscous streaks extending dorsad of vertical furrows; antennae with all 

 segments fused and almost completely filling antafossae; spiracles distinctly winged; 

 tenth abdominal tergum with caudal margin shallowly emarginate on the meson; 

 head with dorsal half entirely glabrous ; length, 1 1 mm. ; on oak ; M-21 . . chloreus Norton. 



3(2) Vertex with fuscous streaks not extending dorsad of vertical furrows; antennae with 

 all segments distinct, but not nearly completely filling antafossae; spiracles not 

 distinctly winged; tenth abdominal tergum with caudal margin not emarginate on the 

 meson; head with dorsal half sparsely setiferous; length, 9 mm. ; Y-133. Nemalus sp. 1. 



4(1) Vertex without a fuscous streak caudad and dorsad of each ocellara; maxillary palpi 

 with segment 2 slightly longer than all the other segments taken together; antennae 

 with four distinct segments; spiracles winged; length, 10.5 mm.; on oak; M-2. 



Nematus sp. 2 



Croesus Leach 



Larvae moderately large, length about 25 mm., body cylindrical tapering 

 caudad on abdominal segments 7-10 and also at cephalic end of prothorax; 

 segmentation distinct; annulation indistinct; third abdominal segment 

 with four or five annulets, annulets 2 and 3 setiferous; tenth abdominal 

 tergum with a pair of low, conical, bluntly rounded caudal protuberances, 

 usually as wide as or wider than high; head flattened on front, rounded, 

 shiny black; antennae distinctly conical with four segments: segment 1 

 incomplete, three times as long as wide, segments 2 and 3 usually complete 

 and not reduced to mere lines on the cephalic aspect, segment 4 peg-like, 

 bluntly pointed, longer than wide at proximal end; maxillary palpi with 

 segment 1, 3, and 4 subequal in length, segment 2 twice as long as segment 

 1 ; larvapods setiferous; spiracles not winged, indistinctly colored; glandubae 

 subsessile or with a short stalk, very wide in diameter more than three 

 times the diameter of shaft of setae; maxacoria developed into a distinct 

 triangular swelling dorso-caudad of cardo, and covered with dark spinulae. 



Croesus latitarsus Norton. — Length, 25 mm.; annulation, 3, 2, 1, 4 or 

 2, 1, 5, 3, 4; larvapods with 4-5 setae and a single glanduba as viewed 

 from side, no markings; tenth abdominal tergum with dark-colored area 



