PHLEBOTOMUS. 201 



one-jointed, and much smaller, generally thin and leaf-like ; the 

 lower pair are one-jointed, but narrow and elongate, slightly 

 curved. These latter arise from a subgenital plate which repre- 

 sents the ventral surface of the ultimate abdominal segment, the 

 upper parts being absent. A flexible, very slender intromittent 

 organ is present, projecting from between the intermediate appen- 

 dages, and consists of a pair of very slender delicate valves, from 

 which a pair of chitinous filaments can be extended. In the 

 female the external genitalia are simple, "consisting of two pairs 

 (a superior and an inferior pair) of compressed, more or less leaf- 

 like appendages covered with sensory hairs " (Annandale). They 

 become distorted in dried specimens, but may be restored by 

 maceration in caustic potash. * There is no horny ovipositor as in 

 PSYCHODI>M:. Legs long and slender, clothed with small scales 

 and pubescence ; coxae lengthened, tibiaB with small apical bristles. 

 The relative lengths of the different joints of the legs vary accord- 

 ing to the species, f Wings rather narrow, varying with the 

 species, lanceolate, or with the tip more or less pointed. Auxiliary 

 vein very short, ending in the costa much before one-third of the 

 wing's length ; 1st longitudinal vein ending at about two-thirds 

 of the wing ; subcostal cross-vein at tip of auxiliary vein ; the 

 2nd longitudinal vein forked near the middle, the upper branch 

 again forked at or before half its length ; 3rd vein originating 

 near base of -ving (at least in basal third of wing), ending at tip 

 of wing ; anterior cross-vein always at basal angle of 3rd vein 

 4th vein forked more or less near its middle, the fork sometimes 

 before, sometimes beyond the fork of the 2nd vein, according to 

 the species ; 5th and 6th veins long, 7th absent or extremely short. 

 All the veins nearly straight or only gently curved. The single 

 basal cell very short. Posterior cross-vein probably present i in 

 all species, but indistinct. All the veins finely pubescent, but 



* In the descriptions of the genital organs under each species I am indebted 

 almost wholly to the work of Dr. Annandale, and to a great extent also in the 

 descriptions of other specific characters. 



t How ranch value may be placed on these proportionate lengths when the 

 differences are very slight it is impossible at present to say. It is best not to 

 place too much reliance on fractional differences. 



J Schiner says it is absent, but so many figures have come before me with t 

 present that it probably does exist though seen with difficulty. It is hardly 

 likely to be present in some species and absent in others. 



Newstead makes several errors in his terminology of the wings. The 

 " subcosta " (or auxiliary vein) does not turn down into the 1st longitudinal, but 

 up into the costa, the small connecting vein being the subcostal cross-vein. The 

 expression that the 2nd longitudinal " extends almost to the base of the wing " 

 is unscientific, as all veins begin at their nearest point to the base of the wing, 

 not vice versa. The 3rd longitudinal does not " originate from the mid cross- 

 vein," but turns out of the 2nd at the usual angle, the anterior cross-vein con- 

 necting it at the point of angulation with the 4th vein. He speaks of the 5th 

 vein " curving upwards and uniting with the 4th" (still apparently considering 

 the vein to start from the margin of the wing instead of from its basal limit) ; 

 whereas if there is a short vein joining the 4th and 5th longitudinal near 

 their bases, it is the posterior cross-vein. His remaining remarks are therefore 

 erroneous, consequent on his misnaming the veins from the first. 



