878 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxvi. 



DIAPHEROMERA MESILLANA Scudder. 

 Diapheromera mesillana Scuddek, Psyche, IX, 1901, j). 189. 

 The original description is here given in full. 



Slenderer than D. femorata, uniform greenish flavous, the antennae infuscated 

 beyond the basal third, the thorax smooth, with an obscure median carina; subajn- 

 cal inferior spine of middle and hind femora rather slight. Mesothorax and metatho- 

 rax (including median segment) of equal length. Seventh and ninth aljdominal 

 segments sul)equal in length and distinctly longer than the eighth, all equal in width 

 and nowhere enlarged, the ninth rather feebly and angularly emarginate, exposing 

 a small, transverse, apically arcuate, supraanal plate; cerci about as long as the ninth 

 abdominal segment, rigidly straight, directed backward and not at all downward, 

 slender tapering, blunt tipped, externally convex, and internally concave. 



Length of body, 55 mm.; head, 3 mm.; antenna?, circa 37 mm.; mesothorax, 12.5 

 mm.; fore femora, 14.5 mm.; middle femora, 11 mm.; hind femora, 13.5 mm. 



Two males. Between Mesilla and Las Cruces, New Mexico, June 30. (A. P. 

 Morse. ) 



MEGAPHASMA, new genus. 



Head .smooth, rounded, .subvertical; antennae more than twice as 

 long as the anterior femora; prothorax one-fifth as long as the meso- 

 thorax and transversely incised; meso- and metathorax subequal in 

 length and with a distinct, though slight, median carina. Middle and 

 hind femora swollen in both sexes, the middle ones somewhat larger 

 than the posterior ones in the male, and both the middle and posterior 

 pairs in both sexes armed beneath on the median line next the apex 

 with a prominent spine and sometimes, at least in the female, with a 

 row of equally large ones extending along the entire length of the 

 femora below. 



This genus is erected for that large Southern walkingstick described 

 by Stal as Diapher'omera dentricus. This insect exhibits characters 

 that are certainly of generic value. The rounded, subvertical head, 

 broad, spatulate cerci and unusually large size will readily separate it 

 from all other of our genera. Diapheromera is the most nearly allied 

 genus, but the characters given in the table will at once separate it 

 from that genus of much smaller insects. 



Ill the United States we have a single species. 



MEGAPHASMA DENTRICUS Stal. 

 Plate LVII, fig. 2, 2a, 2h. 



Di:ipheromera dentricus Stal, Rec. Orth., Ill, 1875, p. 76.— Scudder, Psyche, IX, 

 1901, p. 187; Harpers Mag., LXXXVIII, 1894, p. 456, fig. 1. 



This species was originally described from Opelousas, Louisiana. 

 The following description is made from specimens, male and female, 

 in the U. S. National Museum collection: 



Yellowish brown or fuscous. Head rounded, subvertically attached 



