AMERICAN OOLEOPTERA. 285 



Mesosternum car in ate 1 . 



Mesosternuin not car in ate 13. 



1, — Mesosternuin oblique between tbe coxse 2. 



Meaosternum vertical between tbe coxae 12. 



2. — Third joint of autennse not longer tban the second altcrnata Mels. 



Thi-rd joint distinctly longer ,"?. 



3. — Punctures of elytra in distinct striae 4. 



Punctures of elytra confused, no strial arrangement 10. 



4, — Punctures of the intervals fine 5. 



Punctures of all the intervals and striae equal 9. 



5. — Punctures of strife moderate or coarse fi. 



Punctures of striae fine, intervals obliquely strigose 11. 



6. — Posterior femora of male with the outer condyle dilated in an obtuse 

 unciform process, posterior tibia rather short, not arcuate. 



hiimeralis n. sp. 

 Posterior femora of male broader at middle and angulate or toothed, the 



posterior tibia slender and arcuate valida n. sp. 



Posterior femora of male not dilated, obsoletely serrulate or crenulate, 



posterior tibia slender and arcuate ^ assiinilis Lee. 



Posterior femora of male not dilated, simple, neither dentate nor serru- 

 late 7. 



7. — Posterior tibiae of male scarcely longer or more arcuate than in the 



female puiictatostriata Kby. 



Posterior tibiae of male long, slender and arcuate 8. 



8. — Elytral striae regular. Posterior tibiae of male arcuate near the tip. 



Form oblong, punctures of the alternate intervals closely appro.xi- 



mated dflfficilis n. sp. 



Form oval, punctures of alternate intervals distant collaris Lee. 



Elytral striae irregular, the second and third arcuate, posterior tibiae of 



male arcuate from the knee to tip curvata Mann. 



9. — Outer condyle of posterior femur of male forming an acute hook. 



conferta Lee. 

 10. — Oval, slightly oblong, posterior tibiae of male slightly arcuate. 



paludicola Crotch. 

 11. — Punctures of the intervals nearly equalling the striae but more distant, the 



strigae more evident near the base strigata Lee. 



12. — Posterior femur of male gradually broader, the outer condyle triangularly 



prolonged. Elytra without subhumeral stria obsoleta Mels. 



13. — Mandibles not toothed. Form oblong ecariuata n. sp. 



A. alternata Mels. — Oval, robust, moderately convex, rufo-testaeeous or 

 pale castaneous, moderately shining, legs elongate. Head sparsely punctate. 

 Antennae rather short, the club a little longer than the rest of the antenna, 

 third joint not longer or even a little shorter than the second. Thorax more 

 than twice as wide as long, a little narrowed in front, apex feebly emarginate, 

 base arcuate, hind angles distinct but obtuse, surface sparsely punctate. Elytra 

 a little wider than the thorax, oval, sides moderately arcuate, surface 8-striate, 

 striae erenately punctured, intervals slightly convex obsoletely punctulate, 

 the alternate with coarse, distant punctures. Metasternum alutaceous and 

 sparsely punctate, abdomen sparsely punctate. Length .14 — .16 inch; 3.5 — 

 4 mra. (PI. VII, fig. 1). 



