A Preliminary Revision of the Genus Trisuloides 405 



1. Trisuloides sericea Btlr. (Type.) 



Genitalia (pi. XVI, fig. 5) :— 



Valve long and narrow, lanceolate. The ventral fold develops a 

 process on the inside of the valve. This process is finger-shaped and 

 strongly chitinized. Its base is formed of flexible membrane which 

 is connected with the inner edges of both folds. The process is nor- 

 mally directed anteriorly, but is capable of being raised to a position 

 vertical to the plane of the valve. It is armed with teeth along its 

 proximal edge, which, at the base, projects in a short beak. Uncus 

 stout, broad, apex slightly pointed, and keel on the back slightly 

 developed. 



2. Trisuloides sericea trigonoleuca A. E. Prout. 



Trisuloides trigonoleuca A. E. Prout, Bull. Hill Mus., I, p. 227 

 (1922) (Central Ceram). 



Genitalia (pi. XVI, fig. 8) : — 



Valve as in sericea. Process more strongly chitinized than in the 

 other two forms examined, teeth and beak more prominent. 



3. Trisuloides papuensis Warr. (Probably another sericea subsp., 

 although placed by Hampson in Section I of this genus.) 



4. Trisuloides sericea hawkeri subsp. nov. (pi. XIII, fig. 10). 

 $ , 53 — 57 mm. 



Fore wing almost exactly as in subspecies trigonoleuca, but almost 

 always paler, more filled in with bluish- white between postmedial and 

 subterminal lines (more as in the type-form). 



Hind wing with rather more dark hair at base than in sericea 

 trigonoleuca, but much less than in the type-form ; a subterminal dark 

 shade always present from M 2 to tornus (leaving fringe and termen 

 white), usually more or less continuous to costa and often with dark 

 terminal shading beyond it. 



Undersurface nearly as in subspecies trigonoleuca, but with discal 

 spot and postmedial line usually better developed on both wings. 



? , 63—68 mm. 



Differs from the 3 in the larger size, the rather more obscure 

 markings of fore wing, and especially in the broader border of hind 

 wing (though this varies a little in breadth), which is more as in typical 



