417] LARVAE OF THE TENTHREDINOIDEA—YUASA 99 



mesad and subequal in size to palpi, lacinia thin, small, plate-like; labium 

 comparatively large, flattened; labial palpi inconspicuous, apparently 

 2-segmented; ligula globose and proturding; thoracic legs with coxa large, 

 stump-like, following segments suddenly smaller and slender, trochanter 

 ring-like, femur as long as wide, tibia longer than femur, cylindrical, 

 chitinized, tapering gradually to distal end, tarsal claws broadly curved, 

 sharp; mesothorax and metathorax with a dorsal membranous swelling 

 on each side of the meson; spiracles distinctly and semicircularly winged; 

 tenth abdominal tergum small, convex; anal setae wanting; subanal lobe 

 small, prominently convex. 



SPECIES OF METALLUS 



Head brownish, not concolorous with body, epicranial suture very distinct; dorsal and ventral 

 shields distinct and brown; dorsal shield transverse, covering dorsum of prothorax, 

 proventral shield very large, occupying entire venter between prothoracic legs caudad of 

 and continuous with brown cervacoria, mesoventral and metaventral shields small, 

 transverse, triangular between legs; labium with submentum strongly chitinized, brown 

 with dark carina on meson and along caudal margin, mentum brown, longer than wide; 

 larvapods with crescentric brownish band on cephalic aspect; length, 11-12 mm.; on 

 Rubus; Y rubi Forbes. 



Head pale or whitish, concolorous with body, at least not distinctly colored ; dorsal and 

 ventral shields obsolete, only rarely faintly indicated; labium with submentum broad 

 and without dark median longitudinal carina, depression on meson rarely present, 

 never dark and distinct; larvapods without crescentric brownish band on the cephalic 

 aspect; length, 10 mm.; on Rubus; Y bethunei MacGillivray. 



The larvae of Metallus rubi were described by Forbes, but the original 

 specimens are apparently lost. The description given here is based on 

 specimens in the Cornell Collection. Forty-three larvae of M. bethunei 

 were examined thru the courtesy of Mr. H. G. Crawford of Guelph, 

 Ontario, Canada. 



Subfamily Hylotominae 

 Larvae (Fig. 23) moderately large; body semicylindrical, venter 

 flattened, distinctly wider than high, widest on abdominal segments 1-3, 

 tapering caudad, caudal segments only one half the width of widest seg- 

 ments; yellowish green, spotted or not; segmentation distinct; third 

 abdominal segment with three annulets, all setiferous, often tuberculate; 

 thoracic legs large, spreading laterad, apparently six-segmented inclusive 

 of claws; claws sharply curved, large, distinctly separated from fifth 

 segment by suture and with a large pulvillus-like swelling; larvapods 

 setiferous, on abdominal segments 2-6 and with rudimentary 7th pair, or on 

 2-7 and 10 with rudimentary 8th pair; antennae one-segmented, either 

 conical or button-like, if conical, larvapods on abdominal segments 2-6 

 and 10; spiracles distinctly winged; glandubae obsolete; tenth abdominal 

 tergum without suranal processes. 



