326 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxii. 



Future investig-ations ma_y prove ^achyinervs to be a variety of 

 dorsalh^ but at the present state of our knowledge it can scarcely be 

 considered other than as a distinct species. There is much variation 

 in the development of the elytra and some in the relative length 

 of the posterior feiuora. Rarely some females have the ovipositor 

 distinctly curved upward, l)ut usuall}^ it is straight or even slightly 

 curved downward. 



ATLANTICUS GIBBOSUS Scudder. 



Atlanticus gihhosus Scudder, Can. Ent., XXVI, 1894, p. 180; Cat. Orth. U. S., 

 1900, p. 75.— Rehn, Proc. Acad. Nat. Pei. Philad., 190-1, ( 1905), p. 797.— Kirby, 

 Syn. Cat. Orth., I-I, 1906, p. 181. 



Descr/'jytum. — Head moderately large, not swollen nor deeply 

 inserted into the pronotum; fastigium broad, rounded, not sulcate, 

 broader than the first segment of the antenna. Eyes moderate, not 

 prominent; antenniv slender, basally enlarged. Pronotum large and 

 produced posteriorly over the base of the wirigs more than usual in 

 the other members of the genus, completely covering the wings in 

 both sexes, lateral lobes but moderately deep, almost vertical, posteri- 

 orly broadl}' sinuate; lateral carinas prominent but less acute than in 

 the other species of the genus, converging on the anterior fourth and 

 from there backward diverging and rounded outward, 

 making the disk of the metazoua very elongate-ovate, 

 posteriorly well rounded, nearly semicircular; median 

 carina absent or barely indicated on the posterior 

 margin of the disk; pronotal disk broadl}" convex, 

 without transverse sulci, the anterior margin trun- 

 (iiBBost^. TIP OF cate; prosternal spines elongate and moderately acute. 

 ABDOMEN OF MALE Abdouicn licavy, not or verj" slightly carinate above. 

 Elytra and wings of both sexes concealed beneath the 

 pronotum. Legs moderately stout; posterior femora much swollen 

 on the basal half or a little more, genicidar lo])es well developed, 

 forming close-Ij'ing lamina?, or flattened spines; anterior tibisi? armed 

 above on the outer margin only with three spines; intermediate tibia? 

 spined aliove on ])oth margins and the posterior ones armed Avith a 

 double row of small equal closel}^ set spines above on the apical two- 

 thirds and below^ wdth a few small scattered spines on the median line 

 only. Cerci of the fejnale simple, conical, about four times as long as 

 the })asal width, of the male long and moderately stout, apically 

 slender, curved inward and then upward quite strongl}^, near the base 

 on the inner side armed with a long incurved tooth two times as long- 

 as the width of the cerci at that point (fig. 31); last al)d()minal segment 

 rectangularly Incised; ovipositor about one-fifth shorter than the 

 posterior femora and straight. 



