26 CALIFORNIA ACADEMY OF SCIENCES. 



Tills very distinct species ma}' be recognized immediately 

 by its rather narrow head, broadly rounded beliind, and 

 having the basal angles almost obsolete. The type is a male; 

 the fifth segment is broadly emarginate almost throughout 

 its width at a])ex, the sides of the notch being ver}' strongly 

 convergent and distinctly incurvate, each bearing a por- 

 rected fringe of nine robust, black, short and rather closely- 

 placed spinules; the ]:)orrected process at tiie bottom of the 

 emarginationis very short and rather narrow, scarcely wider 

 than the fimbriate sides; it is broadly and feebly sinuate at 

 apex; sixth segment parabolically emarginate at tip, the 

 notch being slightly wider than deep, exterior angles nar- 

 rowly rounded; seventh narrowly and acutely incised or di- 

 vided along its lower surface as in the preceding species. 



The structure of the posterior tibia3 is peculiar to tlie genus 

 as far as I have observed. 



21 — L. gres^alis i^- sp. — Moderately slender, black, abdomen scarcely paler 

 at tip; elytra slightly piceous; legs d irk castaueous, tibia) toward tip and tarsi 

 paler; anteunaa piceous-black at base, fuscous in the middle, testaceous at 

 tip; puljescence sparse anteriorly, rather long, dense and coarse on the 

 elytra, very fine, dense and short on the abdomen, not conspicuous; integu- 

 ments polished. lleaiJ rather large, as wide as long; base broadly and feebly 

 arcuate, angles broadly rounded; sides j^arallel and distinctly arcuate; epi- 

 stoma broad, moderately produced, truncate; antenual tuberculatious small, 

 rather prominent; labrum moderate, teeth slightly deflexed, small, equilat- 

 ero-triaugular, anteuniB distinctly shorter than the head and prothorax 

 together, second joint slightly shorter and distinctly more robust than the 

 third, distinctlj' longer than the fourth; surface rather strongly convex, 

 finely, very feebly and densely punctate; median line rather wide. Prothorax 

 moderate, slightly longer than wide, very slightly narrower than the head; 

 sides ijarallel, nearly straight in the middle; base broadly and feebly arcuate, 

 broadly sub-truncate in the middle; apex strongly and evenly arcuate at the 

 sides; nuchal emargiuation narrow, not one-third as wide as the disk, rather 

 strongly incurvate; apical angles very broadly rounded, basal slightly more 

 broadly so; disk transversely and moderately convex, very finely mar- 

 gined along the base, rather coarsc^ly, ver^' si)arsely and excessivelj' feebly 

 punctate in the middle, much more finelj', distinctly and densely so at 

 the sides; mcMliau impunctate area rather broad. Elytra at base verj' slightly 

 wider than tlie pronotuni, scarcely wider than the head; sides verj' slightly 

 divergent posteriorly and very feebly arcuate; together broadly, I'ouudly 

 and verj' feebly sinuate behind; disk one-fourth longer than wide, one-third 



