[369] METAMORPHOSES OF ALASKA COLEOPTERA 19! 



deeply bidentate, outer margin evenly arcuate ; outer tooth long taper- 

 ing, rather sharp at apex ; inner tooth shorter, more robust, anterior 

 margin arcuate, curving inwards at right angles. Maxillae stout, ex- 

 ceeding the mandibles in length ; cardo narrow, wedge-shaped ; stipes 

 subquadrangular, the angles rounded, one and one-half times as long 

 as broad, the inner margin ciliate and with a minute conical papilla 

 near the upper angle ; galea not quite reaching to apex of second 

 joint of maxillary palpi, composed of two subequal joints, the basal 

 joint a little the larger ; maxillary palpi four-jointed, first joint broader 

 than long, second and third subequal, fourth slightly longer than third. 

 Mentum projecting, almost reaching the apices of the maxillary stipes, 

 one and three- fourths times as broad towards apex as at base, apex 

 conical ; labial palpi stout, composed of two subequal joints, the sec- 

 ond a little the longer and not divided at the apex. 



Pronotum trapezoidal, narrower in front by one-sixth than at base, 

 nearly as broad at base as long, sides straight with a longitudinal 

 groove close to the lateral margins ; anterior and posterior angles nar- 

 rowly rounded, mesonotum transverse, about one-half as long as 

 pronotum but a little broader and with a small deep fovea on the disk 

 of the scute towards each side. Metanotum similar to the mesonotum 

 but a little broader. Legs of moderate size, strongly spinose. 



Dorsal scutes of first eight abdominal segments transverse, subequal 

 in length, sides distinctly margined, posterior angles acutely rounded; 

 pleural scutes two on each side of a segment, elongate, parallel ; 

 ventral scutes four to each segment, anterior one broadly fusiform, 

 transverse, posterior quadrangular, broader than long, lateral scutes 

 subquadrangular, one on each side of the posterior ; ninth abdominal 

 segment much narrower than eighth, rounded at the sides, finely tuber- 

 culate, emarginate behind ; cerci stout, finely tuberculate, three-fourths 

 as long as eighth segment, diverging slightly, curving gently upwards 

 and bearing dorsally near the middle a pair of small conical pro- 

 jections of which the innermost is the larger. 



Pupa white, except eyes and jaws, which are black ; setae and hairs 

 entirely absent; form elongately ovate, broadest in the middle. 

 Length 14 mm. 



Described from larvae and pupae found beneath beds of moss on St. 

 Paul Island, Alaska, during the month ot August. 



The metamorphoses of none of the American representatives of this 

 genus have been described, so that no comparison is possible with the 

 related American species. The most marked specific characters are 

 in the peculiar structure of the clypeus and the undivided character of 



