288 



Annals Entomological Society of America [Vol. XV, 



Clypetis transversely ^vrinkled or rugose. Antennae reaching as 

 far back as the fifth segment; comparative measures of the joints as 

 follows : 



1st joint, length 0.559 mm. 



2d joint, length 1 . 978 mm. 



3d joint, length 2 . 193 mm. 



4th joint, length 1 . 935 mm. 



5th joint, length 1 .763 mm. 



6th joint, length 1 .333 mm. 



7th-8th joints, length 0.301 mm. 



diameter, 

 diameter, 

 diameter, 

 diameter, 

 diameter 



.0.752 mm. 

 .0.709 mm. 

 .0.623 mm. 

 .0.645 mm. 

 . 645 mm. 



Total length 10 062 mm. 



Mandibular stipe short, scarcely longer than the cardo (Fig. 1); 

 mandibula much higher than broad, with numerous pectinate lamellae 

 (12. .to 14). Intermentum present, divided; postmentum wanting, 

 the gula showing a single ventral ridge, (Fig. 1). 



First segment coarsely punctured dorsally; lateral lobes small, 

 acute, with some 8 or 10 thin, shortened sulci closely packed together 

 in the angle of the lobe. Second segment showing coarse punctures 

 intermingled with faint longitudinal sulci dorsally, the punctures 

 disappearing laterally, while the sulci grow deeper. Following segments 

 distinctly sulcate even dorsally, with only few punctures along the 

 posterior margin, the latter disappearing graduall}^ backwards. First 

 pore on the sixth segment, opening in front of, but close to the suture; 

 further caudad the pores open behind the suture in the center of a small, 

 smooth, indistinctly raised area. Segments without marginal fringe. 

 Karsch devotes a special mention to some depressions to be seen on 

 the segments behind the 18th, which have not been observed. 



Legs of the first and second pairs comparatively short. First 

 sternal plate membranous; coxae of first pair expanded laterally with 

 a slightly sinuous outer margin, and without a cylindrical apical part 

 (Fig. 2). Second sternal plate scarcely chitinised between the stigmatic 

 membranous dimples; tracheal stalks very long and slender, ribbon- 

 shaped; coxae of second pair similar to those of the first, but somewhat 

 shorter. 



Vulvae concealed in lateral, broad and moderately elongate, invagina- 

 tions, their stimmit being on a level with the bottom of the vestibulum 

 (Fig. 3). The operculum, in its anterior aspect, appears as a triangular 

 plate strewn with short setae, the lateral margins of which are bent 

 back perpendicularl\% the outer more than the inner. It is tipped with 

 a peculiar, hood-like appendage (f, 'Figs. 4, 5), laterally compressed, 

 overlapping the mound and bearing few setae. 



The mound is protected laterally by oval valves moderately pilose, 

 standing vertically (ov). Their upper angles are connected by what 

 appears to be (in posterior aspect) a thick, strongly chitinised, quad- 

 rangular pad (h), which is the basal end of the horseshoe plate. The 

 upper forks of the latter, as well as the ridge lying between them, are 

 bent forwards so as to face the concavity of the operculum, thus 

 assuming the position of the anterior truncation. The ridge is wide, 



