-RT.l LARVAE OP AMERICAN TENEBRIONINAE— ST. GEORGE. 13 



vex ventrally slightly flattened, pygidium, subtrapezoidal, apically 

 bicornute. Head thorax, and abdomen covered Avith palef thin, 

 reddish brown hairs. ' ' 



Cranium rounded, nutant, exserted, two-thirds broader than lon^ 

 (from epistomal margin {epi, fig. 3) to foramen oceipitale), broadest 

 median ly, dorsally somewhat convex. Anterior frontal ano-le ifa) 

 rounded. Frons (/) three-fourths the length of cranium, about half 

 as long as wide, with extreme width anteriorly; sides anteriorly and 

 posteriorly convex, medianly concave; frons somewhat triangular 

 near the center two small circular impressions. Epicranial halved 

 {eve) meeting dorsally ; epicranial suture about one-fourth the len<rth 

 ol cranium; the halves ventrally separated by gula {gu, fi<T 7) • epi- 

 crariium with evenly distributed thin setae. Gula distinct, coriaious 

 barrel-shaped, with ventral tentorial pits {tp) just below the middle 

 of the side margins. Clypeus {cl, fig. 3) trapezoidal, widest behind, 

 length to extreme width, one to three; medianly with a transverse 

 deepening, set on each side with two well-developed setae near the 

 lateral margin; anterior third testaceous, posteriorly castaneous-tes- 

 taceous. Labnun {lah) well-developed, movable, transvei-sely rec- 

 tangular, a little more than twice as wide as long, anterior mar<rin 

 slightly crenate, anterior corners rounded; disk between the center 

 and each lateral margin with two large setae,^=^ the one nearer the 

 margin a little more anteriorly placed; on the anterior half of the 

 lateral margins and on the front margin a series of long, thin, slightly 

 chitinized setae and between these many irregularly placed short, 

 rigid setae; behind those on the anterior corner but on the ventral 

 side of labram, usually three shorter, stronger, curved setae. (Fig. 

 1.) Ocelli composed of two groups on each side, just behind the outer 

 antennal ring; both transveree, the anterior one composed of three, 

 more or less fused lenses, the posterior one of two partly fused lenses;' 

 near ocelli a few slender setae. Antenna close behind the mandible', 

 attached to distinctly colored rim below the dorsal mandibular fossa; 

 basal antennal membrane well developed, with posterior portion 

 somewhat corneous; three articles; basal article clavate, about as long 

 as clypeus; second article shorter than first, about as long as labnmi, 

 cylindrical; apical article very small, cylindrical, about one-third \hL 

 length of the second, carrying one short seta; no supplementary ap- 

 pendix from second article beside the apical article. Mandibles (figs 

 2 and 5) both alike, apically trifid {a\ a\ a?), obtusely pointed, with 

 the median tooth {o}) larger and longer; molar part (m) of right 

 mandible with crown bearing four transverse somewhat arched ridges 

 which fit into corresponding cavities of the left molar part; cutting 

 part smooth, ventrally slightly excavated; exterior surface ("the 



^ These two setae occupy always the same position, while the number, size, and position 

 of the rest of the labral setae vary somewhat according to different specimens. 



