42 PROCEEDINGS OF THE NATIONAL MUSEUM vol.84 



Twelve names have been proposed for American species of 

 Tachyjyonis, of which eight were considered valid by Horn. Blatch- 

 ley and Sharp have each described one additional species. Of these 

 14 names 9 are considered valid by the writer, and 8 new ones are 

 proposed. The species described by Sharp in the Biologia Centrali- 

 Americana from northern Mexico is tentatively identified with 

 United States material. 



KEY TO NORTH AMERICAN SPECIES OF TACHYPORUS 



1. Elytra with oblique discal spot black maculipennis 



Elytra without oblique discal black spot 2 



2. Elytral suture with series of submuricate punctures 3 



Elytral suture without submuricate punctures 8 



3. Body convex and robust, prothorax not decidedly broader than 



elytra 4 



Body narrow and depressed, prothorax obviously broader than 



elytra nitidulus 



4. Body above black, apex of elytra alone paler nanus 



Color piceous to pale, not as above 5 



5. Pronotum paler at sides or at base 6 



Pronotum unicolorous, pale rulomus 



6. Basal fifth only of pronotum paler tehamae 



Base and sides of pronotum indefinitely paler 7 



7. Eighth sternite of female broadly rounded californicus 



Eighth sternite of female feebly emarginate stejuegeri 



8. Pronotum uniform in color throughout 9 



Pronotum maculate or at least clouded at center 12 



9. Elytra with large scutellar black spot and last abdominal seg- 



ments indistinctly darker elegans 



Elytra without large scutellar spot, abdomen unicolorous 10 



10. Elytra marked with darker areas 11 



Elytra unicolorous jocosus 



11. Marginal series of five punctures; no additional discal puncture 



at humerus snyderi 



Marginal series of five punctures; with an additional discal 

 puncture near the humerus temacus 



12. Basal fourth of pronotum and basal half of elytra black pulchrus 



Thorax maculate at center or in apical half 13 



13. Each elytron with sutural black spot extending to apical fourth___ oregonus 

 Elytra without large black discal spot 14 



14. Elytra with an additional humeral puncture just inside the 



lateral series 15 



Elytra without additional humeral puncture acaudus 



15. Marginal series of three punctures arizonicus 



Marginal series of four punctures 1^> 



16. Elytra Avith median discal pair of large punctures alleni 



Elytra with a single median discal puncture mexicanus 



The species herein described have the following characters in com- 

 mon ; these have been omitted from the specific descriptions, but they 

 apply to all the species listed : 



