266 Transactions. — Zoology. 



divergent ; fourth longitudinal almost straight ; fifth longi- 

 tudinal arcuated ; sixtli incomplete, not reaching to apex of 

 inner marginal cell, situated some distance from fifth longi- 

 tudinal. 



This genus is evidently closely allied to Ditomyia, but 

 differs from it in the point of origin of the third longitudinal 

 vein. 



Nervijttncta nigrescens, sp. nov. Plate VIII., fig. 1. 



Length of antennae, 0-055; dimensions of body, 0-170 x 

 0-030; expanse of wing, 0-155 x 0-057. 



Antenme 2 + 15 jonited ; first joint of scapus short, 

 cyathiform, fuscous ; second more than twice the length of 

 tlie first, fuscous, but with a broad cinereous boi'der on 

 the upper end ; all joints of flagellum black, slightly de- 

 creasing in length and diameter from the base upward ; 

 each joint with several small scattered hairs, and a zone 

 of stiff hairs about the middle point. Palpi four-jointed — 

 first joint small, nearly round ; second joint long and 

 rather broad, black, with long black hairs at its anterior 

 end ; third joint black, more slender, nearly naked ; last 

 joint cylindrical, brown, with a fevv stout black hairs at 

 its anterior end. Eyes large, emarginate. Ocelli three, 

 middle smaller than the two lateral, situated nearly in a 

 row. Eyes almost contiguous, behind the antennae. Vertex 

 dark-brown, densely pubescent. Anterior portion and sides 

 of thorax bright-golden, covered with golden hairs; central 

 portion of thorax and scutellum dark-brown, the former 

 ornamented with a few long stiff black hairs. Metathorax 

 brown, but lighter than the mesothorax. Lower portioias of 

 ephnera almost black. Abdomen very narrow anteriorly, 

 biit broadening posteriorly, consisting of seven segments; an- 

 terior portion of each segment dark-brown ; posterior margin 

 has a narrow band, smoky-grey in colour ; all segments covered 

 with moderately-long black hairs. Legs rather long and thin ; 

 anterior coxae light-yellow, posterior coxae becoming brown at 

 the tips ; femora dark-brown, long and narrow, covered with 

 short stout black hairs ; anterior tibia slightly longer than the 

 femur, bearing one short spine at its end; posterior tibia much 

 longer, ornamented with two spines, and bearing scattered 

 short stiff bristles ; all tibiae and tarsi nearly black ; first 

 joint of tarsus very long, othei-s decreasing gradually in size, 

 thickly clothed with very short black hairs. Wings nearly 

 entirely brown, surface clothed with scattered black slender 

 hairs. Auxiliary vein rudimentary ; first longitudinal nearly 

 three-quarters the length of the wing; second and third 

 longitudinals with a common but very short petiole arising 

 from the apex of the inner marginal cell ; petiole of second 



