46 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 89 



Accessory glands (AcGl). — Typically a bifurcate or paired in- 

 vagination on the venter of the ninth segment, usually forming glands 

 having a coUeterial function. 



Gonopods (Gp). — The appendages of the eighth and ninth ab- 

 dominal segments. Each gonopod, when complete, consists of a basis 

 (Lb) bearing a proximal, medial gonapophysis (Gon), and a distal 

 stylus (Sty). 



Ovipositor (Ovp). — The egg-laying organ formed of the gonopods. 



First valvifers (iVlf). — The basal plates or lobes of the ovipositor 

 supporting the first valvulae ; derived from the bases of the first pair 

 of gonopods, and provided v^^ith muscles arising on the eighth tergum. 



Second valvifers {2Vlf). — The basal plates or lobes of the ovi- 

 positor supporting the second valvulae ; derived from the bases of the 

 second gonopods, and provided with muscles arising on the ninth 

 tergum. (Usually called " coxites" of the ninth segment.) 



First valvulae (iVl). — The gonapophyses of the first gonopods, 

 forming the ventral blades of the ovipositor. 



Basivalvulae (bv). — Small sclerites sometimes differentiated at the 

 bases of the first valvulae. 



Second valvulae (2VI). — The gonapophyses of the second gono- 

 pods, forming usually the dorsal blades of the ovipositor, but the 

 inner blades in Orthoptera having a third pair of valvulae. 



Third valvulae (3VI). — The distal lobes of the second valvifers, 

 derived with the latter from the bases of the second gonopods ; usually 

 forming a sheath for the shaft of the ovipositor, but in most Orthop- 

 tera a third (dorsal) pair of blades in the ovipositor. 



Intervalvulae (iv). — Sclerotic remnants of the ninth sternum be- 

 tween the second valvifers. 



Egg guide. — A median process sometimes present on the end of the 

 eighth sternum behind the invaginated gonopore, serving to direct the 

 eggs into the channel of the ovipositor between the bases of the first 

 valvulae. 



Genital chamber (GC). — An inflection of the body wall at the base 

 of the ovipositor above the end of the eighth abdominal sternum, form- 

 ing a pouch containing the gonopore and the opening of the sperma- 

 theca ; in Panorpidae the genital chamber is closed below by the ninth 

 sternum and opens above the latter. 



Vestibulum (Vst). — A cavity formed by inflection of the body wall 

 above the seventh sternum when the latter is prolonged beyond the 

 eighth, thus concealing the true genital chamber above the usually 

 reduced eighth sternum. 



