18 THE ANAL APPENDAGES. 



a point of attachment to the saw, but it may be also 

 said to support its outer valve, which is only loosely 

 attached to it, and consequently is capable of being 

 moved about by the insect with some freedom. It 

 undoubtedly serves as a sheath to protect the apical 

 part of the saw, but I believe it acts also, in some way, 

 as a tactile organ. 



The ovipositor, then, is composed of three pairs of 

 organs, or six pieces in all, the two-jointed outer 

 sheath, the support, and the saw itself. The saws are 

 joined near the top, and on the lower side, by a 

 muscular band, but the connection between them is 

 often not very close. They are thus capable of being 

 separated, and form a passage for the eggs to go 

 down. Above the saw may be seen a pair of chitinous 

 processes, between which the tube of the poison gland 

 enters. 



The Male Anal Appendages. 



The last abdominal segment projects on the lower 

 side and forms a kind of hollow, in which the male 

 genital armature lies. Like the female organs, they are 

 easily extracted, and are of a tough, horny, or leathery 

 texture. At the base is a thin ring (PI. XV, fig. 14, 

 3), by means of which the parts are brought into con- 

 nection with the inner sexual organs. The parts next 

 to this ring are two double- jointed valves, united by 

 membrane at the base. They are curved round on 

 the inner side so as to form a hollow tube, in which 

 the double-valved penis lies (PI. XV, fig. 14, 2, and 

 fig. 14 a), forming, in fact, a sheath for it. The basal 

 part is hard, horny, glabrous, and deep brown in 

 colour. The apical portion is much smaller, more 

 membranous, lighter coloured, and hairy externally 

 (fig. 14, 1) ; it is usually somewhat triangular or oval 

 in shape, and possesses some flexibility. The shape 

 of the organs may be seen by reference to the figures 

 (PL XV, fig. 14). 



