some Oriental Nycteribiiila?. 217 



uortliy that in P. Jletc/ieri tlie ventral surface of the thorax 

 is not convex from front to back, as it markedly is in several 

 species of the genus. The most remarkable character of 

 P.fletcheri as a species is the form of the dorsal abdominal 

 segments of the ? ; their plan recalls that of Nycferibia 

 (^c/-ocAo/<V//«)/?-y6/-j.mihi, described from Assumption Island, 

 South-west Indian Ocean *. In the complete absence of eyes, 

 the length and slenderncss of its legs, the different form of 

 its ventral thoracic plate, and in many other points, N.frytri 

 is entirely different from P. fletcheri, but the abdominal 

 terjiites of the ? are arranged on the same plan, though 

 differing in details. In both species the ? has a small 

 basal tergitc. with hind margin sinuate or emarginate in the 

 middle and a series of strong bristles at the hind angles ; in 

 both there is a large second tergite, longitudinally divided 

 into two halves, each of which is produced behind. P. Jlet- 

 cheri is absolutely distinct from any Nycteribiid that 1 have 

 seen, and 1 am unalde to make it agree with descriptions or 

 figures of any that I have not seen ; it is dedicated to its 

 collector, Mr. T. Bainbrigge Fletcher. 



2 a. Pcnicillidia fletcheri, xar. pumila, var. n. 

 (PI. X. fig. 0.) 



Length circa 1*5 mm. 



Closely resembling the preceding, but very much smaller. 

 Even allowing for the shiunken state of the abdomen in 

 most if not all the specimens, there is a great difl'erence 

 in size; when var. ^Mw?7fl is viewed side by side with the 

 type-form, it appears only about half as large. 



In the ^ the only other difference appears to be in the 

 long bristles in the median part of the hind margins of 

 abdominal tergites 4, 5^ and 6; these are very long in the 

 small form, proportionately longer than in the large J of 

 the type-form. 



In the ? there are more decided differences (Pl.X. fig. 5). 

 The narrow posterior part of teryite 2 is a little narrower in 

 var. piimila ; the 4 long bristles on the hind margin of each 

 half are very long, appearing longer in proportion tiian in 

 the type-form ; the side-margin of each half, instead of 

 having only 4 ra'.her short bristles at about the middle, has 

 4 or 5 longer ones, widely spacexl, extending from a little 



* At the time of printinp: this paper my de.scription of N. frtjeri is not 

 yet published ; but it will appear shortly in Trans. Linn. Soc. Louden, 

 f-er. 1* Zool. V(il. xvii. 



