4 Transactions of the Society. 



meres, with long virga, and various indistinct chitinous plates in 

 tlie prseputial sac. 



Zacher does not figure, but describes the genitalia of Mecomera 

 sp., from Brazil. If it is a true Mecomera, it is most probably 

 M. hrunnea Serv., the only known species. It appears to have 

 the complex armature of the preputial sac which is so common a 

 feature in the Labiidse. 



I will now discuss a few species the genitalia of which have 

 not yet been described. I have only examined the manubrium in 

 two species — in Irdex nitidipennis and Chxtospania pittarellii — 

 in both it is longer than broad, gently narrowed, and rounded at 

 tlie tip. 



Irdex nitidipennis Borm. 



Typical lanceolate metaparameres ; virga more than twice as 

 long as the metaparameres, bilobed at the apex, with no discernible 

 basal vesicle, and one or two long and narrow chitin-plates in the 

 prseputial sac (PI. I, fig. 2). 



Nesogaster rujiceps Erichs. 



Metaparameres rather broad at base, lanceolate and recurved ; 

 virga very long and straight, no basal vesicle discernible, termi- 

 nating apically in a complex dilated chitin-structure, with one or 

 two plates, and one spanner-shaped plate (PI. I, fig. 1). 



Marava doddi Burr. 



Metaparameres broad and parallel-sided, abruptly narrowed 

 and acute at the tips ; virga with very feebly chitinized basal 

 vesicle, then curved in the form of a U, opening into an inflated 

 chitinous area, with an elongate, apically dilated, narrow chitin- 

 plate (PI. I, figs. 3 and 4). 



Spongovostox ruber Bor. 



Metaparameres narrow, acuminate and recurved at the tips ; 

 proparameres with spongy dilations ; virga very long, about four 

 times as long as the metaparameres, undulated in basal portion ; 

 prseputial sac with round denticulate plate. 



The specimen is from the Kamerun, and is in erection (PI. I, 

 fig. 5). 



Spongovostox conradti Burr. 



Metaparameres narrow and recurved, acuminate, but no 

 spongy dilatation ; virga very long, undulate and coiled, with 

 hooked chitinous basal armature (PI. I, fig. 6). 



