26 E. B. WiLI-IAMSON 



slightly shorter appendages alone distinguish it from the geographically 

 widely separated T. trifida. 



In the three males available and in the single female provisionally refer- 

 red to this species there are invariably three cells in the anterior row of 

 cells in the anal loop ; in the male there are two cells posterior to A between 

 the anal loop and the anal triangle, and in the female there are four cells 

 posterior to A between the wing base and the anal loop; in the front wings 

 of males, one wing has a single double cell between Mo and Rs. two wings 

 have three double cells, and one wing has four double cells ; in all the other 

 wings of both sexes there is a single row of cells throughout between AL, 

 and Rs. 



The auricles of the second segment of the male are each armed with 

 three denticles or with three and the vestige of a fourth. 



Material examined: Costa [Rica, Banana River (P. P. C, forest, upper 

 reservoir, November 9, 1909, one male, A. N. S.) ; Venezuela, La Fria, Dept. 

 Tachira (in forest, April 17, 1920, i male, E. B. W.) ; British Guiana, 

 Bartica (H. S. Parish, May 27, 1901, i male, O. S. U.). See also discussion 

 above of specimens in the de Selys Collection, where Martin's six types of 

 satynis are considered in detail. As explained there, these types were re- 

 ceived for study long after this paper was completed. During the prepara- 

 tion of this paper Mons. Severin kindly sent me one of the types of satynis, 

 but this one happened to be the Santo Domingo specimen. On the basis of 

 this examination satynis was reduced to a synonym of trifida in my paper, 

 and I described my material as a new species. With the examination of all 

 six of Martin's types it is now possible to save his species and I have design- 

 ated one of these specimens as the type of satyrus. 



Gynacantha laticeps, new species 



Abdomen male 33-33.5, female 35-38; hind wing male 32, female 34-37; 

 superior appendage male 4.5 ; stigma front wing 2.25-3. 



Male and female. — Labium and face dull pale yellow, slightly darker 

 above, and occupying most of the frons above, which has a darker greenish 

 shade, so the brown T-spot is reduced and inconspicuous ; frontal vesicle 

 dark brown ; occiput greenish yellow ; rear of head dull pale yellow, black 

 margining the eyes above, and this joined with a broad black bar to the 

 foramen. 



Prothorax pale brown or greenish brown, the posterior edge yellowish 

 green. 



Thorax green ; if any markings are present in life they have not survived 

 post-mortem changes. 



Abdomen not constricted, brown or yellowish brown, marked with pale 

 (green or yellow or both) and black; i and sides of 2 apparently largely 

 green, i darker above apically ; 2 with AD very narrow and extending from 

 the base to and across the subapical transverse carina, but ending before the 

 extreme margin of the segment and interrupted at the median transverse 

 carina; a basal trace of AD on 3 ; MD present as a triangular spot on either 

 side on 2-7; sides of 2-7 slightly if any paler than the dorsa, no definite 



