ART. 2 BEETLE LARVAE OF GAIvERUCINAE BOVING 39 



sclerites fused into a square median plate with a few setae on each 

 side. Poststernellar area ( = spinisternum) triangular, distinct, only 

 slightly chitinized. 



J/esothorax atid nietatliorax (fig. 15). — Interior prescutal sclerite 

 almost fused with the corresponding sclerite of the opposite side, 

 sagittal light line very distinct, two setae on each side; exterior 

 prescutal sclerite small, with two or three setae. Interior and exte- 

 rior scuto-scutellar sclerites similar to the interior and exterior pre- 

 scutal sclerites in .size, form, coloration, and the number of setae. 

 Alar sclerite large, with about five setae. Spiracular area of meso- 

 thorax pushed somewhat forward and partly located below the pro- 

 thoracic shield; area normally placed in metathorax; one seta pres- 

 ent. Ej^ipleural sclerite with one seta. Prehypopleural sclerite 

 (=episternum) larger, flatter, and more chitinized than in prothorax, 

 one seta present; posthypopleural soelerite ( = epimeron) as in pro- 

 thorax. Eusternal sclerite oval with two or three setae on each side. 

 Each sternellar sclerite with one seta. Mesothorax with a distinct 

 poststernellar area (=^spinisternum) ; metathorax without this area. 



First to eighth abdominal segments (fig. 15). — Dorsally divided 

 into three distinct areas, namely, prescutum, scutum, and scutellum; 

 ventrally also divided into three areas, namely, eusternum, sternel- 

 lum, and poststernellum ; poststernellum constituting an interseg- 

 mental band. Interior prescutal sclerite fused with that of the other 

 side into a single, median, transverse, compound sclerite, on each side 

 with four or five light and thin setae ; exterior prescutal sclerite small, 

 carrying a single seta. Scutal sclerite located straight behind exterior 

 prescutal sclerite and like this of small size and carrying but one seta. 

 Interior and exterior scutellar sclerites in size, form, and arrangement 

 similar to the interior and exterior prescutal sclerites. Parascutal area 

 with both the anterior and the posterior sclerites well developed, 

 closely approaching each other, forming together a frame surrounding 

 a large supraspiracular gland, and each having two or three setae. 

 Epipleural and hypopleural sclerites well developed, convex, carrying 

 half a dozen setae. Eusternum with a large, oval, unpaired sclerite 

 carrying three or four setae on each side. Sternellar sclerite distinct, 

 paired, with two setae. Poststernellar area without sclerite. 



Ninth dbdom^inal segment. — Pygidial shield transverse, elliptical, 

 small, about one-third as wide as long and about half as wide as the 

 eighth abdominal segment ; a dozen setae on each side in the margin, 

 and a few setae in the central portion of the shield. Ventral part 

 of the segment with a transverse row of three indistinct sclerites, one 

 medianly located, and one on each side; three small setae on each side. 



Tenth abdo7nin<d segment. — With a ring-shaped chitinization at 

 base. 



