X0 .H24. EEVISION OF THE MEL AXOPLISC UDDER. 45 



the front margiu truncate, the hind margin subrectangulate; prozona 

 and metazona of subequal length, the sulcus separating them distinct 

 but not deep, suddenly augulatc in the middle by the emargination of 

 the prozona, tbe posterior sulcus of the prozona arcuate or angulate so 

 as to approach it in the middle, the middle sulcus subparallel to this 

 but more nearly transverse and crossing the middle of the prozona, the 

 front of the prozona in no w$iy elevated to receive the head. Pro- 

 sternal spine quadrate, appressed," broadly truncate; interspace between 

 mesosternal lobes subquadrate, a little longer than broad in the male, 

 the reverse in the female, the metasternal lobes attingent over some 

 space (male) or approximate (female). Tegmiua and wings fully devel- 

 oped, the former with scarcely any ampliation of the costa near the 

 base. Fore and middle femora but little more gibbous in the male 

 than m the female; hind femora not very long, the hind tibiae with ten 

 spines on the outer side. Margin of subgenital plate of male straight 

 from the base, which is not ampliate, a little elevated at the apex; 

 cerci styliform, about as long as the supraanal plate, the furcula nearly 

 obsolete. 

 The genus is confined so far as known to Mexico and Central America. 



AIDEMONA AZTECA. 

 (Plate I V, fig. 1.) 



Platyphyma azteca SAUSSURE, Eev. Mag. Zool., 1861 (1861), p. 161; Ortk. Xov. 

 Amer., II (1861), p. 12. WALKER, Cat. Derm. Salt. Brit. Mus., IV (1870), 

 p. 716. THOMAS, Rep. U. S. Geol. Surv. Terr., V (1873), p. 223. 



Pczotettix aztecus STAL, Bib. K. Sv. Vet.-Akad. Handl., V (1878), No. 9, p. 10. 



Aidemona azteca BRUNNER, Rev. Syst. Ortli. (1893) p. 145. 



Brownish fuscous above, sometimes deepening to blackish fuscous, 

 especially on the upper half of the lateral lobes of the pronotum, testa- 

 ceous below, often deeply infuscated. Head mostly testaceous, heavily 

 punctate throughout excepting on the vertex, where the puncta are 

 obscure and subdued, and where the color is dark; fastigiuin with more 

 or less elevated but rounded lateral walls; frontal costa slightly 

 widened just above the ocellus; antennae testaceous, more or less 

 infuscated, especially toward apex. Pronotum heavily and almost 

 equally punctate throughout, both on dorsum and lateral lobes, but less 

 crowded on the posterior half of the lateral lobes of the prozona, and 

 with a small, free, glabrous patch above on either half of the prozona; 

 lower half of the lateral lobes testaceous, in greater or less contrast to 

 the blackish upper half, the darker portion widening on the metazona; 

 but while this feature is sometimes very marked, in specimens in which 

 the testaceous under surface becomes flavous, it is sometimes scarcely 

 to be detected, so infuscated may the lower half become. Tegmina 

 far surpassing the abdomen, rather slender, well rounded apically, 

 griseous from a profuse and rather minute fuscous flecking on a semi- 

 pellucid base, the flecking more or less confluent in the basal third; 



