CORA.—ARCHILESTES. 45 
misled into supposing the black to extend much farther forward on the dorsum of the 
abdomen than is stated above. By carefully following (with a lens) the black lateral 
border of the segments and the characteristic triangular anteapical prolongation of 
this black on the segments named, it will be seen that the dorsal blue has existed in 
life as described, but has faded almost to black after death. 
2. Cora semiopaca. 
Cora semiopaca, Selys, Ann. Soc. Ent. Belg. xxi., Compt. Rend. p. xxi (1878)*; Bull. Acad. Belg. 
(2) xlvii. p. 408 (1879)*; Kirby, Cat. Odon. p. 118 (1890) °. 
Hab. Panama, Chiriqui (coll. McLachlan: 1 3; coll. P. P. @.: 12), Volcan de 
Chirigui 2500-4000 feet (Champion: 3 3). 
On comparing material before me with the descriptions of this species! ?, it is to 
be noted that the nodus is not placed halfway between the base of the front wing and 
the extremity (outer end) of the pterostigma, since double the distance from base to 
nodus falls upon the middle of the pterostigma, or upon its inner end. ‘The ptero- 
stigma surmounts 34 to 6 cells. Front wings with 28-32 antecubitals, the thicker one 
of which is the 10th, 11th, or 12th; 24-30 postcubitals. Hind wings with 21-26 
antecubitals, the 9th, 10th, 11th, or 12th thicker; 26-29 postcubitals. Abdominal 
segment 10 with a dorsal conical prominence similar to, but less developed than, that 
of C. marina. 
Subfam. 2. LHSTINA. 
The two genera of this fauna are separable as follows :— 
Nodal sector parting from the principal sector within 12 cells beyond the 
nodus; quadrilateral broader, the basal side about one-half as long as 
the posterior (or inferior) side on the front wings. . . . . . . . . J. ARCHILESTES. 
Nodal sector parting from the principal sector at from 3 to 5 cells beyond the 
nodus ; quadrilateral narrow, the basal side one-third (or less) as long as 
the posterior side on the front wings . . . . . . . .. . . « « & Lesres. 
These two genera are closely related, and differ from the only other known American 
genus of this subfamily (Ortholestes, Calvert) in possessing (inter alia) supplementary 
sectors between the median and the short sectors. | 
ARCHILESTES. 
Archilestes, Selys, Bull. Acad. Belg. (2) xiii. p. 294 (1862); Kirby, Cat. Odon. p. 159 (1890). 
Archilestes is a characteristic genus of the Mexican and Central-American fauna, 
whose distribution is indicated under A. grandis below, as the only other species, 
A. californica, McLachl., is known by a single individual only from California. 
