144 PROCEEDiyOS OF Tin: XATIONAL MUSEVM. vol XX. 



a little contracted in tlie middle; fuinihi consistiiij? of a pair of rather 

 distant, njoderately slender, scarcely taperinjj, blunt, dark deiiticula 

 tioiis, overlyinjjf the outer slopes of the subinedian ridjijes of the supra- 

 anal idate, and extendiuf? over the ])late by only a litt'. more than the 

 length of the last dorsal segment; eerci strongly com];ressc(l bull. ite 

 just beyond the base, the buHate portion broader than long and exte 

 riorly very strongly and longitudimilly convex, beneatli sulcate, the 

 whole bullate portion abruptly narrowing and terminating in a com 

 pressed, indirected. round tipi)ed,e(iual and short linger, falling a little 

 short of the tip of the supraanal plate: subgenital plate short, sub- 

 conical, and apically very broad by the abrupt rounded production of 

 the a])ical margin, the process of about e([ual height and posterior 

 breadth, entire. 



Length of body, male, IG mm., female, 22 mm.; antennae, male, 0.5 

 mm. (est.), female, (» mm.; tegmiua, male and female, mm.; hind 

 femora, male, 10.25 mm., female, 12 mm. 



One male, 4 females. Si>nora, Mexico, A. Schott, Mexican Boundary 

 Survey. 



This species differs from the preceding two in the uniformity of the 

 pronotum, which does not expand posteriorly, and has a uniformly 

 shar]) median carina throughout; it is also lighter bodied and less 

 heavily marked. 



2. FLABELLIFER SERIES. 



Ill this series, one of the few which combines macropterous and bra- 

 chypterous forms, the male prozona is feebly or distinctly longitudin<il, 

 occasionally (juadrate, the interspace between the mesosternal lobes of 

 tlij same sex varying from quadrate to half as long again as broad, or 

 somewhat more. The tegmiua are either fully developed, though at 

 most but slightly surpassing the hind femora, much and irregularly 

 maculate; or half as long as the abdomen, heavily marked in the dis- 

 coidal field and subacuminate; or shorter than the pronotum and then 

 apically rounded. The length of the tegmiua in each species, however, 

 is tixed. The hind tibiae are blue, with nine to eleven spines in the 

 outer series, or, in some brachypterous forms, red, with ten to thirteen 

 spines in the outer series. 



The supraanal plate is triangular, rather longer than broad, with no 

 or slightly developed transverse ridges. The furcula is minute or sul>- 

 obsole e, exce[)t in a single instance where it is small. The cerci are 

 broad, often excessively broad and tlabellate, enlarging from the base 

 toward the middle, at least in the macropterous forms, rarely as much 

 as twice as long as broad, broadly rounded apically. The subgenital 

 ;»i{ite is short and broad, sometimes with a slight apical tubercle, the 

 lateral margins straight, the apical margin not elevated, or only in a 

 single instance. 



M. rUeyiunis is the most aberrant form, having very brief tegmiua, 



