CHETSOPLECTEUM.— ACOLASTTTS. 303 



is very slender and meets the median at the origin of its second branch. Besides the 

 type, C. otriades (Hew.), we only know of the following species and one undescribed in 

 our collection. 



1. Chrysoplectrum perniciosum. (Tab. LXXVII. figg. 6, 7, 8 s .) 



Eudamus perniciosus, Herr.-Schaff. Prod. Syst. Lep. iii. p. 65 (1868) '; Plotz, Stett. ent. Zeit. 



1882, p. 88 2 . 

 Carystus epicincea, Butl. & Druce, Cist. Ent. i. p. 113 (July 1872) 3 ; P. Z. S. 1874, p. 368 4 . 



Alis fascia fere unicoloribus, anticis fascia transversa mediana venis quadripartita costam haud approximante 

 semihyalina : subtus ad basin leviter viridi lavatis, fascia transversa ut supra sed macula bifida ad costam 

 alba, macula ad angulum analem albo circumcincta, margine interno ad angulum analem late albo ; 

 posticis maculis duabus indistinctis discalibus albidis, ciliis indistincte albis, plica costali obvia. 



Bob. Mexico, Atoyac (H. H. Smith) ; Nicaeagua, Chontales (Belt) ; Costa Bick(Van 

 Patten 3 *); Panama, Chiriqui (mus. Staudinger). — Amazons Valley, Rio Negro 2 . 



Dr. Staudinger has kindly lent us a specimen from Chiriqui which he had compared 

 with the type of E. perniciosus. We have one Nicaraguan specimen from Belt's 

 collection which agrees precisely with the Chiriqui insect and with the type of Carystus 

 epicincea from Costa Rica. We have also several specimens from Mr. Bates's collection 

 from San Paulo on the Upper Amazons as well as from Para ; these are undoubtedly 

 referable to the same insect. Its northern range extends to Mexico, whence we have a 

 single male specimen taken at Atoyac by Mr. Smith. 



C. perniciosum is strictly congeneric with C. otriades *, the type of the genus, and has 

 the tarsal spines to the hind legs developed in the same way. 



The male genitalia of C. perniciosum have a truncated short tegumen cleft at 

 the end, the scaphium being highly developed. The harpes terminate in a single 

 isolated spine, above which the outer edge is thickened and strongly serrate. (See 

 Tab. LXXVII. fig. 8.) 



We have dissected two specimens — one from Mexico, the other from the Amazons 

 Valley, and they agree in every respect. 



ACOLASTUS. 



Polygonus, Hiibner, Ex. Schmett. ii. t. 144 (1822-26) (nee Schum. Molhisca, 1817). 

 Acolastus, Scudder, Rep. Peabody Ac. Sci. iv. p. 71 (1872) ; Wats. P. Z. S. 1893, p. 25. 



This genus, containing a single species, is closely allied to Proteides, but differs inter 

 alia in the shape of its wings and in the general style of coloration. There are no 

 tufts of hair on the surface of either wing, no conspicuous spines on the under surface 

 of the hind tarsi, nor any costal fold to the primaries of the male. The second median 

 segment of the primaries is about twice the length of the first segment ; the cell is 



* From an examination of the type of Thymele euphronius, Hab. (Le Nat. x. p. 181), kindly lent us by 

 Dr. Staudinger, we find that it belongs without doubt to Hewitson's Eudamus otriades. 



