214 Journal New York Entomological Society. t^'o'- xxvi. 



Table of the North American Species of the Tribe Mastogenixi. 



1. Presternum with distinctly limited, subtriangular antennal cavities and dis- 



tinct carina on each side of middle ; posterior margin of hind coxal plates 

 feebly emarginate ; third joint of antennie small : i)rothoracic sculpture 

 reticulate; color black, elytra bluish . .Trigonogya reticulaticollis Schaef. 

 Prosternum without antennal cavities and without carins at middle, 



Mastogenius 2 



2. Posterior margin of hind coxal plates more or less sinuate or emarginate; 



the exterior and interior angles slightly prominent ; front convex and 



more or less distinctly impressed 3 



Posterior margin of hind coxal plates oblique and internally rather broadly 

 dilated ; color jeneous ; front convex and sometimes with feeble median 

 impression; third antennal joint shorter than fifth.. M. robustUS Schaef. 



3. Third antennal joint shorter than fifth ; prothorax widest below middle ; 



coarsely and rather closely punctate, punctures as large, or a little larger, 

 as those on elytra ; intervals between the large punctures very finely and 



densely punctulate M. puncticollis Schaef. 



Third joint of antennas about as long or slightly longer than the fifth ; inter- 

 vals l)etwecn the large prothoracic punctures not densely punctate, 

 smooth 4 



4. Prothorax widest at apical third ; a small fo\eiform impression near middle 



of side margin and a very fine and faint median impressed line which 

 reaches neither base nor apex ; third joint of antennae scarcely more than 



half as long as the fourth M. impressipennis Fall. 



Prothorax widest at about middle, without small foveiform impression near 

 side margin at middle and without median impressed line ; third joint of 

 antennse more than one half as long as the fourth. . .M. subcyaneus Lee. 



Haltica scutellaris Oliv. 



Specimens which tindotibtedly are this species occur at Browns- 

 ville, Texas. It is very near our H. rufa and colored like that species 

 but the upper surface is very shining and much more finely punctate 

 and the antennal joints are a little longer and narrower with the third 

 and fourth joints nearly equal in size. 



