ASILUS (SENSU LATO NEC LATISSIMo) 64.3 



margin as mentioned later on in the characters of the belly, while in the female it 

 forms part of the ovipositor. Bristles often entirely absent, but a row of bristles 

 or strong bristly hairs frequently occurs close to the hindmargins of the segments 

 or may be limited to the sides of these pra3hindmarginal rows, or be limited to 

 the sides of the pnehindmargiual rows on the basal segments only ; when the bare 

 hindmarginal hems are wide or obvious these bristles are ranged in a row close 

 to the bare hindmargin ; no other bristles occur upon any other part of the dorsal 

 surface of the aljdomen. Belly often with long pendent sparse fine pubescence on 

 at least the basal segments, and sometimes with minute bristly pubescence on the 

 end segments (Asi/iis), and sometimes with a few bristles just before some of the 

 hindmargins in the male, while the shape of the hindmargin of the eighth segment 

 in the male often gives strong characters and indicates close relationships, as it is 

 sometimes quite straight, sometimes more or less widened, and sometimes produced 

 into a spoon or trowel-like projection upon which considerable bristly pubescence 

 may exist ; the hindmargins of other ventral segments are sometimes more or less 

 dropped from the ventral line. Genitalia of the male conforming to one main type, 

 though with manifold variations in the form and size of the various parts. There are 

 two pairs of lateral lamellas, and one basal ventral process near or enclosing the 



Senis ; the upper and larger pair of lamellae are called the " claspers," and the 

 ifferent forms of their upper, under, and especially inner, sides, afford valuable 

 specific (and j^erhaps generic) characters. The claspers commonly have a more or 

 less conspicuous dentation on their inner side about their middle, so that when placed 

 in such a position that their points meet they enclose (on the end half) a more or 

 less oval or circular space and this part of the claspers is called the " forceps " ; the 

 claspers also before this dentation usually enclose a small oval space, but when, 

 there is no middle dentation the two arms of the claspers would together form the 

 forceps. The lower and smaller pair of lamellae lie under the basal part of the 

 claspers and are merely called the " lower lamellae " ; they either lie against the 

 arms of, or push their curved tips up between, the claspers, and as their shape does 

 not seem to vary much they are not of so much value for distinctive purposes. The 

 basal ventral process may be called the " middle piece," and is a small narrow strap- 

 shaped lamella, which lies between the claspers in a more or less sloping position 

 and usually bears a moderate pale pubescence, but as its form seems to atibrd but 

 few obviously distinctive characters it has been but little referred to. The penis 

 can seldom be examined without softening and opening the genitalia, but forms 

 a three-pronged fork in which the prongs vary specifically both absolutely and 

 relatively, while sometimes its length and direction are obvious enough to notice. 

 The genitalia of the female are composed mainly of the ovipositor which is formed 

 out of the eighth and ninth abdominal segments and is ended by two small lamelke 

 which extend out (generally) from the tip of the ninth segment. The simplest and 

 most typical form shows a conical two-jointed ovipositor with two lamellce projecting 

 from its tip, but as the parts are usually distinctly modified this simplest form 

 occurs but seldom ; the terminal lamellae are usually crooked, and occasionally 

 are of considerable size and bent downwards (Antijxdvs), in which case the eighth 

 abdominal segment does not form part of the ovipositor. The ninth segment is 

 often emarginate or notched at its end, and both the eighth and ninth segments 

 (like the previous ones) are divided into an upper and an under half -segment ; as a 

 rule the upper half of each segment is distinctly separated, but the segments of the 

 under half are usually indistinct ; in many species the under half of the eighth 

 segment is very much enlarged, especially in those females which have the ovipositor 

 strongly compressed and of the well-known triangular or sabre-shaped figure. 

 It is usually not difficult to distinguish the two separated upper pieces, the tei'minal 

 lamellae, and the single undcr-piece, of which the end part is usually characterised by 

 peculiar sculpture and sometimes by strongly characteristic pubescence. When the 

 upper part of the ninth segment is notched on the hindmargin (fig. 358) the terminal 

 lamellaa are wedged in this notch. The shape, comparative size, and scidpture of 

 all these parts of the female genitalia deserve the closest examination as they provide 

 very positive distinctions. The ovipositor when compressed is often formed of not 

 only the eighth and ninth segments, but also of the seventh, or even of the sixth 

 and seventh segments {Xeoitamua). 



The markings of the abdomen are usually less distinct and less characteristic 

 than those of the thorax, and are also ditficult to describe because they vary so much 

 according to the point of view ; the contrast in different lights is so great that those 



