137 



is described by Mr. Westwood in the greatest detail, and with 

 continual references to those portions of the descriptions published 

 by his predecessors, which are either vague, or incorrect, or in which 

 they are contradictory to each other. The principal points which he 

 has endeavoured to elucidate, in addition to the transformations which 

 these insects undergo, are the distinction of the sexes, and conse- 

 quently the sexual characters and the diiFerent organization of the 

 abdomen in the sexes ; the structure of the mouth, antenncs, and eyes ; 

 the separation of the metasternum and the abdomen ; the situation and 

 construction of the spiracles ; and the nature of the serrated organs 

 between the base of the anterior and intermediate legs. The sexual 

 distinctions appear especially to have been misunderstood, and the au- 

 thor takes great pains to explain them in each of the species respec- 

 tively which he has been enabled satisfactorily to examine. 



Mr. Westwood concludes his Paper by a Synopsis of the Species 

 of the 



Genus Nycteribia. 



Nycteribia Sykesii. Nyct. rufo-picea, thoracis tegumento dor- 

 sali abdomineque obscuri albicantibus ; hoc tuberculis minutissi- 

 mis nigris undique tecto tuberculis quatuor majoribus in quadran- 

 gulo centrali dispositis, segmentis (unico basali excepto) destituto, 

 apiceque pilis rigidis ferrugineis elongatis obtecto ; pedibus elon- 

 gatis subcompressis paullu dilatatis, breviter setosis ; femoribus 

 magis ferrugineis, coxis anticis elongatis tibiisque apicem versus 

 attenuatis ; pectinibus thoracis elongatis ; oculis e tuberculis qua- 

 tuor compositis. (?) 

 Long. Corp. lin. 2^. — Species maxima. 



Hab. in India, Orientali. — In Mus. D. Sykes. 



Nycteribia Hopei. Nyct. abdomine concolore nitido, in medio 

 obsolete 5-articulato, ovato-conico-depresso, segmento ultimo co- 

 nico-truncato, apice lateraliter setigero subtiis stylis duobus conico- 

 elongatis inflexis armato. {^) 

 Long. corp. lin. 2. — Prsecedenti valde affinis, at minor. An 



illius mas .' 



Hab. in IndiS Orientali, apud Bengaliam. — In Mus. D. Hope. 



Nycteribia dubia. Nyct. fusco-castanea, pedibus magis casta- 

 neis ; coxis anticis elongato-conicis, femoribus tibiisque subcylin- 

 dricis; thorace subttts irregulariter rugoso ; pectinibus thoracis 

 lateralibus elongatis; abdomine (" $ " Latr. ^ ?) ovato, 6-annu- 

 lato, segmento postico conico-elongato postice attenuato et truncato. 

 Long. Corp. circiter lin. 2., Latr. 

 Nycteribia Blainvillii, Latr., in Nouv. Diet. d'Hist. Nat., tom. xxiii. 

 nee Leach. 



Hab. in Insula Isle de France dicta. Latr. — India ? — In Mus. olim 

 Latreille. 



The alleged diversity of sex, the diflference of habitat, and the 

 nearly cylindrical legs, induce the belief that this species is distinct 

 from the last, with which however it offers a close resemblance both 

 specifically and sexually. 



