BEMBIDIIN/E 7 



than the prothorax, which is generally cordiform, with the side mar- 

 gins not abruptly grooved; frontal sulci oblique but never in con- 

 tact at apex 17 



17 Frontal sulci never more than partially double, each elytron usually 

 having two small distinct pale spots XIV (quadrimaculatum) 



Frontal sulci evenly and closely double throughout their extent, rather 

 strongly converging; elytra nearly as in the assimile group. 



XV (sulcatum} 



1 8 Body small and more or less ventricose, nearly as in the two pre- 

 ceding groups, the elytra, typically, having each a small external 

 pale spot near the apex; pronotal side margins abruptly though not 

 coarsely grooved XVI (assimile} 



The Icevigattim, tigrinum and sulcatum groups are each repre- 

 sented by a single species, and the ephippigerum and semistriatum 

 groups each by two. The largest groups are those represented by 

 erasum, ustulatum and variegatum, the last named being by far the 

 largest of the genus in America, though in the European fauna 

 the ustulatum group assumes this role. The proper identification 

 of ustulatum Linn., has caused a good deal of discussion and re- 

 search, but it is known now to be typified by a species having a 

 cordate prothorax, much narrower than the elytra, the latter with 

 large nubilous paler humeral and subapical areas and two dorsal 

 punctures on the third stria. No species of the sphceroderum group 

 seems to have been known to Mr. Hay ward, but at the time he 

 drew up his monograph it was represented by three or four dis- 

 tinct Mexican forms, described by Bates in the "Biologia." In 

 the material at hand there are a few additional species from North- 

 ern Mexico, Arizona and New Mexico. It has the aspect of a dis- 

 tinct genus, but is allied to the European Philochfhus. 



Group I litorale 

 Subgenus Odontium Lee. 



Bracteon Bedel. 



This group was divided into two in the Hay ward monograph, 

 but a small section consisting of punctatostriatum Say, hesperium 

 Fall and a new one described below, is so evidently intermediate 

 between the litorale type, having two large flattened and chagrined 

 depressions between the second and third striae, and the coxendix 

 type, having no trace of these depressions, that there can be but 

 little doubt that they all form a single subgeneric group, as main- 



