546 Mr. D. Sharp ami Mr. F. Muir on the Comparative 



Chalcolepidius albertisi (PI. LXVII fig. 156). 



Median lobe slender, chltinous above and on sides, membranous on 

 ventral face ; median orifice near tijs on ventral face, base produced 

 into two long median struts. Lateral lobes a little shorter than the 

 median lobe, flattened horizontally and deeply cleft on outer edge 

 about half way down (a) nearly dividing them into two pieces ; their 

 bases meeting on the dorsal aspect. Basal-piece very long and divided 

 into two sclerites, one long V -shape {!>), a more basally placed piece 

 running round the basal edge (c) ; dorsal aspect membranous. 

 Internal sac undifterentiated. 



The aedeagus in Elateridae is as a rule a generalised 

 trilobe type, becoming compressed and asymmetrical in 

 Anisomerus. The division of the lateral lobes and basal- 

 piece into two in Chalcole2ndius is interesting. It is a 

 more differentiated form of the family, which seems to be 

 on the whole rather monotonous and uninteresting. 



Family THROSCIDAE. 



Forms examined : Throscns dermestoides L., England. 

 Lissnmvs hicolor Clievr., Mexico. 

 Figs. 157 and 158 PI. LXVII. 



The aedeagus of this family is a tri-lobed form near to Elateridae. 

 In T. dermestoides, fig. 157, the median orifice is on the ventral 

 aspect near to the base and the basal-piece is large and well de- 

 veloped. In Lissomus hicolor (PI. LXVII figs. 158, 158rt) the basal 

 piece is membranous (m) in the centre on the ventral aspect, and 

 the chitin forms a ring ; the median orifice is on a membrane on 

 the ventral aspect of the broad, flattened median lobe. The internal 

 sac is undifterentiated. 



Family EUCNEMIDAE. 



Form examined : Hemiopsida mastersi Macl., Australia. 

 Fig. 159 PI. LXVII. 



Median lobe short, forming a pointed, chitinous plate on the dorsal 

 aspect, prolonged into two long median struts. Lateral lobes large, 

 consolidated together at the base to form a tube, the distal ends 

 spatulate and twisted. Basal-piece very small, forming a round 

 sclerite on the ventral aspect. Fig. 159 shows the internal sac {■is) 

 partly protruding. 



Near to the Elaterid type, but the detached, small 

 basal-piece may prove to be distinctive. 



