NOVITATES ZOOLOGICAE XX11I. 1916. 125 



including Venezuela and Trinidad. There is also a pair in the Tring Museum 

 labelled Rio de Janeiro, and another ? ticketed " Brazil," but it is perhaps 

 advisable to await confirmation of this record before accepting it as correct. 

 Anyhow, A. insulata is an essentially Caribbean species. The ranges of the other 

 species are much more restricted. 



In colour insulata varies from cream-colour to buff-yellow. The black suffusion 

 of the frons is restricted to the lower third, and is sometimes vestigial only. The 

 pectinations of the central segments of the antenna are in the 3 about as long as 

 the shaft of two segments. The main distinctions are found in the genitalia, which 

 are built up on the same plan in all three species, but exhibit very striking differ- 

 ences in the detail. The supra-anal hook, which is morphologically the tenth 

 tergite, and is usually termed the uncus in descriptive Lepidopterology, is nearly 

 always visible without dissection. But in order to get a clear view of the other 

 sclerites it is necessary to remove the eighth segment, or at least that apical portion 

 of it which projects over the following segments, forming a sort of cylinder or cavity 

 into which the organs of copulation are retracted. When the eighth tergite has 

 been made somewhat flexible by a little wood-naphtha or weak alcohol, a sharp 

 longitudinal cut at one side and a cut across the back usually enables one to lift the 

 integument up and bend it towards one side without breaking it altogether, leaving 

 the ninth and tenth segments exposed to view. 



The ninth tergite is dorsally produced into a pair of long processes (P 1 in our 

 text-figures), which are hollow, bear long stiff scales usually pasted together, and 

 contain probably scent-glands. The processes project over the widened and 

 centrally-flattened apical portion of the ninth tergite and overlap the base of the 

 tenth tergite (or uncus). In insulata (text-figs. 1 and 2, P 1 ) they are three times as 

 long as they are broad, being widened distally on the outer sides with the apex 

 rounded off. The pleurite of the ninth segment forms the side-clasper, consisting 

 of the valve (V) and the harpe (H). The valve (text-figs. 1, 2, 3, V) is thin, i.e. 

 weakly chitinised, and evidently serves more as a cover than as an organ of pre- 

 hension. Its shape in A. insulata is represented in text-fig. 2, the real outline 

 being distorted in a view from above (text-fig. 1), and from below (text-fig. 3). 

 The harpe (H) is detached from the valve, except at the base. It is as long as the 

 clasper in insulata, slender, with the apex rounded and more or less widened, the 

 proximal portion of the ventral margin being irregularly notched (cf. text-figs. 2 

 and 3). On the ventral, membranaceous or semi-membranaceous, portion of the 

 ninth tergite, inside of the clasper towards the penis-sheath, there is on each side 

 a short, soft, club-shaped process (P 2 ) studded at the apex with long bristles 

 (text-fig. 2). This organ, which recurs in various shapes throughout the family, 

 though not everywhere, is apparently of a sensory nature. The tenth tergite (x. t.) 

 of these species is a simple process, widest at the base, more or less convex above, 

 and gradually curved downwards, its under surface being concave. In insulata the 

 apex is sharply pointed and subcarinate above. There is no separate, projecting 

 sclerite below the anus homologous with the tenth sternite, this sternite simply 

 forming part of the integument extending between the penis-sheath and the anus. 

 The penis-sheath (Pen) is very large in all three species, and internally armed with 

 one strongly chitinised spiniform love-dagger. 



In the female the differences most easily seen are those presented by the 

 eighth sternite, which lies behind the orifice of the vagina (Vg) and in front of the 

 anal segment (which is formed by segments ix and x being completely fused). In 



