1904.] NATURAL SCIENCES OF PHILADELPHIA. 51 



The iTi,ale of this species is, as noted by Saussure,* ahiiost identical 

 with that of D. femorata, but the female can readily be distinguished 

 by the comparatively robust limbs and short conoid cerci. The 

 female from Alta Mira is interesting, as it possesses two short spinous 

 interocular processes, but is in every other detail perfectly typical of 

 the species. The male from Guaymas has the right anterior limb 

 aborted. Saussure has recorded this species from near Tampico. 



Genus SERMYLE Stai.^ 

 1875. Sermyle Stal, Recensio Orthopterorum, III, pp. 23 and 76. 



Type. — As restricted,*** Acanthoderus mexicanus Saussure. 

 Sermyle physconia n. sp. 



Types. — c^ and 9 ; Piedras Negras, Costa Rica. (Schild and Burg- 

 dorf.) [Cat. No. 6,975, U. S. N. M.] 



Allied to S. mexicana (Saussure), but differing in the female in the 

 reduced expansion of the fifth abdominal segment, the much longer 

 sixth, and the less compressed seventh, eighth and ninth segments. As 

 the male of mexicana has been imperfectly described, comparison is 

 hardly possible. From S. cetolus (Westwood) it can readily be dis- 

 tinguished by the smaller size and shorter genital opercule. 



d^ . — Size medium ; form elongate ; surface subglabrous. Head rather 

 elongate, but slightly expanded anteriorly; interspace between the 

 eyes with a pair of erect dentiform tubercles; eyes subcircular, de- 

 cidedly prominent; antennae over twice the length of the anterior fem- 

 ora, basal joint depressed. Pronbtum longitudinal, over half again as 

 long as broad, median transverse sulcus deeply impressed. Mesonotum 

 slender, two and a half times the length of the head and pronotum 

 together, subequal (except posteriorly), rounded. Metanotum (with 

 median segment) equal to three-fourths the length of the mesonotum, 

 similar in shape to the mesonotum but more robust ; median segment 

 subquadrate, equal to one-fifth the length of the metanotum alone. 

 Abdomen slender, elongate, all segments longitudinal; seventh seg- 

 ment compressed, but apically dilated; eighth segment slightly longi- 

 tudinal, apically compressed, practically fused with the seventh; 

 ninth segment slightly over half the length of the seventh, bullate, 

 moderately expanded, apical margin with a comparatively deep median 



^ Miss. Scientifiq. Mexiq., Orth., p. 165. 



' The genus Pseudosermyle, created by Caudell {Proc. U. S. Nat. Mas., XX^T, 

 p. 867), includes the forms having trifid cerci in the male. The Mexican Bac- 

 teria tridens Burmeister is accordingly a member of the genus Pseudosermyle. 

 No such foliaceous lobes are developed in this genus as are found in true 

 Sermyle. 



'» Vide Caudell, Proc. U. S. Nat. Mus., XXVI, p. S67. 



