AC^NITUS. 43 



quadrate, the basal area narrower and the petiolar short, laterally 

 sinuate, apically glabrous, and the lateral areas irregularly costate ; 

 apophyses large aud obtuse ; spiracles large, linear, aud circum- 

 costate. Scutellum black, deplanate and finely punctate throughout, 

 laterally carinate to the centre, with its basal fovea quinque- 

 carinate; postscutellum glabrous. Abdomen much narrower than 

 the thorax, with its apical halt' strongly compressed and laterally 

 clavate; three or four basal segments nitidulous aud impunctate ; 

 apices of all the dorsal and ventral segments very narrowly 

 testaceous ; basal segment elongate, centrally sulcate to its apical 

 third, with a row of punctures on either side and the spiracles a 

 little before its centre ; gastrocoeli obsolete, extreme anus testa- 

 ceous. Legs : anterior pair entirely stramineous, with the apices 

 of the bifid claws alone infuscate, front calcaria strongly curved ; 

 hind legs stout and elongate, black, with the trochanters flavescent, 

 femora except at apex fulvous, and the tarsi, except the simple 

 claws and basal half of first joint, stramineous. Wings uniformly 

 infuscate-hyaline with the external margin hardly darker ; radix 

 rufesceut, tegute black, nervelet obsolete ; the bifenestrate second 

 recurrent nervure intercepting the cubital very distinctly before 

 the single submarginal nervure; the first recurrent of hind wings 

 subopposite and emitting the apically curved nervellus from very 

 distinctly above its centre. 



Length 13 millim. 



SIKKIM (Col. O. T. Bingham). 



Type in the British Museum. 



This insect may prove to be the alternate sex of that last 

 described ; but, in view of the divergences of their frontal and 

 venational conformation, the scutellar and tibial colour and alar 

 intumescence, it were better for the present to treat them as 

 distinct, especially since the only individual I have seen of 

 A. alecto was captured by Bingham in Sikkim at an altitude of 

 4000 feet in April, 1894, or some thirteen hundred miles from 

 the Nicobar Islands. 



12. Acaenitus xanthorius, sp. n. (Plate I, fig. 1.) 



<$ 2 . A flavous species, with sparse black markings, and the 

 alar apices alone infumate. Head flavous, with the ocelli, apices 

 of mandibles, the distinct occipital border narrowly in the centre, 

 and in $ the entire vertex, black ; frons and vertex deeply and 

 isolatedly punctate, the former with the scrobes large, glabrous, 

 and centrally strongly carinate to the coarsely and rugosely 

 punctate face; clypeus similarly sculptured, apicallv truncate, 

 and in J not basally discrete. Antenna filiform and abruptly 

 obtuse apically, black, with the scape and basal flagellar joints 

 flavidous beneath ; in J , the 19th to 21st joints (far beyond 

 the centre) stramineous. Thorax evenly and distinctly punctate, 

 flavous ; of d 1 immaculate, of $ with a broad vitta on either 

 side of the deeply impressed notauli, a spot on the longitudinally 



