NY^rPHALINiE. 275 



Genus DIADEMA. 



Diadema, Boisd.,^ *' Voyage de 1' Astrolabe — Lep., p. 135 (1832)," and Faune 

 Eiit. de Madag., p. 39 {1833); Westw. (" Sfctiou A. Sub-Section a, 

 Divn. *" of Diadema), Gen. Diurn. Lep., ii. pp. 279-280 (1850); 

 Wallace, Trans. Ent. Soc. Lond., 1869, p. 277; Trim, (part), Rhop. 

 Afr. Aust., i. p. 150 (1862). 



Imago. — Head large, as wide as tliorax, densely liairy and scaly, 

 and with a long tuffc of hairs in front ; eyes large, prominent, smooth ; 

 palpi rather stout, elongate, widely separated, divergent, porrected 

 horizontally, not rising above middle of eyes, densely scaly, — second 

 joint long, with a dense fringe of short, stout hairs superiorly and 

 internally, — terminal joint of moderate length and rather broad, with 

 the tip rather blunt ; antennce rather short, slender, with an abruptly- 

 formed, subovate, slightly-flattened club, bearing a minute acute point 

 at its extremity. 



Thorax moderately stout, clothed beneath and anteriorly above 

 with short hair, posteriorly above with long liair. Fore-wings elon- 

 gate, produced apically ; costa considerably arched ; hind-margin con- 

 cave about middle, slightly sinuated ; posterior angle prominent but 

 rounded ; inner margin slightly emarginate in middle ; costal nervure 

 strong, terminating at some distance beyond middle ; first and second 

 subcostal nervules arising not far from each other, a little before extre- 

 mity of discoidal cell, — third at a considerable distance beyond cell, 

 and terminating at apex ; upper disco-cellular nervule very minute, — 

 middle one rather short, very strongly curved or bent towards base 

 of wing inferiorly, — lower one well developed, rather long, slightly 

 curved, united to third median nervule at a little distance beyond 

 its origin; discoidal cell rather short, truncate. Hind-wings broad, 

 rounded, somewhat truncate ; costa very convex close to base, thence 

 moderately arched ; hind-margin sinuated ; anal angle marked, rather 

 prominent ; inner margins strongly convex to considerably beyond 

 middle, forming a broad, deep groove completely receiving abdomen, 

 thence markedly divergent ; costal nervure extending to apex ; dis- 

 coidal cell very short ; upper disco-cellular nervule (forming base of 

 radial nervule) united to second subcostal nervule not far from the 

 latter's origin, — lower one very slender but quite distinct, slightly 

 angulated towards base of wing, joining median nervure at or a little 

 before origin of second and third nervules ; internal nervure rather 

 short, terminating just at end of convexity of inner margin. Fore- 



^ Mr. W. F. Kirby [Syn. Cat. Dkirn. Lep., 1871, p. 224) has abandoned Diadema as a 

 name preoccupied, and has substituted for it Hubner's title of Hypolimnas. It is true 

 that the name Dimlema was proposed by Schumacher in 1817 for a genus of Cirripede 

 Crustacea, but it has not been adopted in that class, being synonymous with Lamarck's 

 gemis Coronula, founded in 1802. (See Darwin, Monorjr. Cirrip., 1854, p. 397.) 



