DISMOKPHIA. — ACMEPTEBON. 179 



subtus coloribus lsetioribus ; posticis area anteriore flavescente, macula magna in cellula et fascia irregulari 

 a costa ad medium marginis externi transeunte, fuscis, triente anali aurantio-fulva (nee ferruginea). 

 ? femmae D. sorornce similis, sed anticis vittula elongata mediana a basi angulum analem versus extendente 

 ferruginea, ad finem cum maculis discalibus semihyalinis ; posticis area mediana ochracea tincta et semi- 

 byalma : subtus coloribus omnibus dilutioribus maculisque majoribus, area mediana ochracea. 



Hah. Costarica (Van Patten 1 ); Panama, Volcan de Chiriqui, 4000 to 6000 feet 

 (Champion). 



A single female of this species was included by Messrs. Butler and Druce in their 

 list of Costa-Rican butterflies under the name of D. cordillera of Felder, but the 

 acquisition of two male examples from the Volcano of Chiriqui we think clearly shows 

 that none of them are referable to the southern species. The rufous streak over the 

 median nervure of the primaries on the upper surface in both sexes readily distinguishes 

 D. myris from D. sororna ; moreover, the former has a large ochraceous spot in the 

 middle of the secondaries beneath, though this latter character is more pronounced in 

 one of our specimens than in the other. 



Mr. Champion's two male specimens were taken at an elevation of between 4000 and 

 6000 feet above the level of the sea. 



ACMEPTERON, gen. nov. 

 We use Pieris nemesis of Latreille as the type of this genus. The male differs from 

 Dismorphia in having the branch of the subcostal of the secondaries emitted at the end 

 of the cell instead of beyond it, though the female resembles Dismorphia in this respect. 

 The middle discocellular is bent to a right angle, each section and the upper and lower 

 discocellulars being subequal, but the latter in the female are much abbreviated. The 

 harpagones of the male terminate in two strongly chitinous dentate lobes. The bursa 

 copulatrix of the female has a spinous patch rounded at each end and somewhat 

 constricted in the middle. 



The four species we include in this genus are all closely allied ; three of them are 

 peculiar to Central America, and the fourth, A. nemesis, has a wide range over the 

 slopes of the Andes in South America. 



1. Acmepteron nemesis. 



Pieris nemesis, Latr. Humb. & Bonpl. Obs. Zool. ii. p. 78, t. 35. ff. 7, 8 \ 



Leptalis atthis, Doubl. in Gray's Zool. Misc. p. 75 \ 



Dismorphia nemesis, Butl. & Druce, P. Z. S. 1874, p. 362 3 ; Staud. Ex. Schmett. p. 26 4 . 



c? alis anticis nigro-fuscis et valde angulatis, venis ad basin, maculis tribus obliquis ultra cellulam, aliisque 

 apicem propioribus (et interdum duabus elongatis infra venam medianam) flavis ; posticis plaga mediana 

 subovali fusca sericeo-fusco circumcincta, regionem anteriorem usque ad venam medianam occupante, 

 triente anali et macula apicalem versus flavis, litura infra venam medianam et margine apicem versus 

 fuscis, ciliis flavis : subtus anticis sericeo-fuscis, plaga mediana pallide fusca, apicibus rufescentibus et 

 griseo atomatis ; posticis ruf escenti-fuscis, fascia irregulari maculosa fere obsoleta a margine interno ad 

 costam extendente pallidiore maculisque indistinctis, aliis griseo atomatis angulum analem versus flavo 

 notatis et rufo atomatis. 



2a2 



