40 E. B. W11.IJAMSON 



Gynacantha nervosa Ranibur 

 6, 7, II, iz, 19, 20, 2T,, 25, 26, 31, 35, 36. 



Abdomen male 50-54, female 52.5-57; hind wing male 47-54, female 

 52.5-56; superior appendage male 6.5-7.5, f female 5.4-6.3; stigma front 

 "'ing 4-5-57- 



Wings hyaline to brown tinged ; in some cases, and this seems especially 

 true of tenerals or younger individuals, irrespective of locality, there is a 

 faint yellowish longitudinal stripe, which suggests the wing coloration of 

 bifida, but in such specimens of nervosa the yellow line is not darkened and 

 more conspicuous basally as it is in bifida. 



The margins of the genital fossa of segment 2 in the male are armed 

 on each side, anterior to the point of convergence, with eleven to nineteen 

 scale-like denticles, mostly in a single row, about twelve being the most 

 usual number; and the auricles are armed with five to eight denticles, five or 

 six being the usual number. The female abdominal appendages are linear 

 at the base, the apical third or more slightly widened, suggesting in a way 

 a modified male appendage of this group; the expanded portion with a 

 dorsal median longitudinal carina or low keel; maximum width .6; extreme 

 apex acute. 



Dr. Calvert has kindly furnished me with notes on living colors of two 

 Costa Rican males. Where these descriptions are not in accord the differ- 

 ences shown are indicated in parentheses. Eyes olive green above, very 

 pale brown 'below (dark brown above, bordered anteriorly with a line 

 of pale green, below which the eye is pale brown ) with distinct black 

 pseudopupillae ; face and lips very pale brown ; f rons superiorly pale green 

 with a black T-spot ; vertex black with a pair of very small greenish spots; 

 occiput pale bright green ; rear of head very pale green, eye margins black. 

 Dorsum of thorax pale green, sides with some green but mostly (also jjectus 

 and legs) pale brown (most of sides of thorax and pectus very pale lilaceous). 

 Dorsum of abdomen dark brown with small (pale) green dorsal spots (or 

 transverse lines) as follows: a dorsal apical transverse green stripe on i ; 

 a middorsal longitudinal green line on 2 ; three transverse stripes, all inter- 

 rupted middorsally, at anterior end, middle, and posterior end of 2 ; 3-8 

 similar to 2, lacking the longitudinal green stripe, but the transverse stripes 

 mere lines, the middle stripe at the transverse suture (the apical spots or 

 interrupted stripes absent or almost so on 7 and 8) ; 9 with (without) 

 apical spots; 9 and 10 with (without) traces of the anterior spots; ventral 

 surface of abdomen pale lilaceous (probably usually brown, E. B. \V.), a 

 pale brown longitudinal stripe on ventral part of each tergite of 2-8. 



The following notes were made on living colors of specimens taken at 

 Palma Sola. Male. — Eyes above dark green, a blue transverse line in front 

 on either side, shading below into pale yellowish brown wMth six to eight or 

 more brown pseudopupillae ; rear of head narrowly black above, remainder 

 light dull yellow. Prothorax flesh colored, middle lobe brown. Thorax 

 above with a very narrow light yellow mesothoracic collar, this collar 

 bordered above and below with light reddish brown, dorsum green, rather 

 dull, indefinite antehumeral brown areas fading out above; mesepimeron and 



