NO. II LARVAE OF THE ELATERID BEETLES GLEN lOI 



mostly along lateral margin ; mediosternite bearing from 4 to 8 setae 

 and 2 very faint impressions meeting medially ; sternum undivided on 

 eighth segment. 



Ninth abdominal segment (fig. 21, g, h), exclusive of urogomphi, 

 about as long as eighth abdominal segment and at least three- fourths 

 as wide; five-sixths to seven-eighths as long as wide; widest an- 

 teriorly ; width at anterior margin of caudal notch about three-fourths 

 to five-sixths greatest width of segment. Dorsum convex, sloping 

 downward from front to back. Dorsal plate {dpla) irregularly 

 wrinkled ; densely punctate, punctures moderately large and deep ; a 

 pair of paramedian impressions {pirn) converge posteriorly but do 

 not meet; lateral impressions usually obliterated by submarginal de- 

 pression; usually without setae (rarely with 2 small setae anteriorly) 

 except at lateral margins, which are strongly raised and carinate, 

 bearing 2 or 3 blunt "teeth" {to), only the most posterior being 

 prominent; transverse impression {trim) dark and strong, continuing 

 completely across segment. Tergite continues uninterruptedly laterally 

 and on posterior ventral surface ; densely punctured throughout with a 

 few larger pits anteriorly on lateral aspects; usually with from 15 

 to 25 setae on each side, sometimes more. Distance between posterior 

 margin of pleural area and anterior margin of caudal notch approxi- 

 mates one-eighth of total length of segment (exclusive of urogomphi). 

 Pleural area {pi) large, consisting of transversely striated membrane 

 except at each anterior end, where there is a large pleurite which is 

 posteriorly attenuate and bears i to 3 setae. Sternum of 2 sclerites, 

 separated anteriorly by median longitudinal suture and posteriorly 

 by tenth abdominal segment; each sclerite with about 10 setae, mostly 

 in irregular row around tenth abdominal segment. 



Urogomphi {ur, fig. 21, g, h) large, separate, bifid near tip, punc- 

 tulate; prongs short, outer prong larger. Inner prong {ipr) small, 

 fleshy with horny tip; arising from medial or medioventral margin 

 of distal one-third of urogomphus ; projecting caudad with upturned 

 tip (sometimes eroded) ; without setae or tubercles. Outer prong 

 {opr) short, robust, three times as wide as inner prong and longer; 

 projecting dorsocaudad, terminating in blunt round tip (sometimes 

 very broad at tip) ; without setae or tubercles. Undivided part of 

 urogomphus usually with linear depression on ventral aspect at point 

 of separation of prongs; i large seta on lateral aspect arising from 

 deep cup with raised anterior margin ; 4 to 6 setae ventrally, usually 

 arranged as follows: i or 2 setae in depression between bases of 

 prongs, I or 2 setae mesad to this depression and anterad to base 



