Anatomy of the Male Genital Tithe in Coleoptera. 501 



points basally. The aedeagus in Lathrobmm is extremely irregular 

 and asymmetrical in structure. 



Stemis speciclator (PI. Ill figs. 70, 70«). 



Median and lateral lobes on same plan as Paederus rijxirins. 

 Internal sac large, with two chitin strips (a). These chitin strips 

 are continuations of the chitin of the ventral surface of the median 

 lobe. 



Osorius sp. (PI. LIV fig. 72) from Trinidad, apparently has the 

 lateral arms entirely missing, or reduced to a narrow, small band 

 slightly distal of the median foramen on the ventral side (II). The 

 median lobe is bulbous with the dorsal side semi-membranous and 

 the ventral distal edge pointed. The internal sac is large with two 

 diverticula near base, one bearing short hairs on the tip, and a large 

 curved diverticulum at end, ventral of the opening of ejaculatory 

 duct. 



Nodynus leucofasciatus. 



Median lobe bulbous at base, chitinous on ventral side and drawn 

 out distally to a point, the dorsal side being membranous ; median 

 orifice at distal end on dorsal side ; the median foramen small, on 

 ventral side and about the middle. Lateral lobes fairly broad, 

 pressed against sides of the median lobe and projecting slightly 

 beyond tip, attached to median lobe on ventral side of edge of 

 median foramen. Internal sac without chitinous armature. 



This is very Silphid-like, but the absence of the basal-piece 

 separates it from that group. 



Olophrnm piceum is very like Nodymis, the lateral lobes being 

 flattened and curved. Internal sac long, flattened and coiled up in 

 the median lobe ; its surface covered with hair-like scales. 



Zeptochirus, sp. 



Median lobe tubular, curved ventrally near the base ; semi- 

 chitinous on dorso-basal part. Median orifice on dorsal side of tip ; 

 median foramen small, near base on ventral isde. Lateral lobes 

 small, about one-fifth the length of the median lobe. Internal sac 

 large, but not examined. 



Zirophorus hicornis (PL LIV fig. 73). 



Has a thin, slightly flattened median lobe, strongly chitinised 

 and curved at the base, and semichitinous along the dorsal basal 

 part (m). The lateral lobes are articulated to the curved base and 

 consist of narrow lobes free along their whole length. Median 

 orifice at distal end, median foramen at base. Internal sac short 

 and without armature. 



