NO. II LARVAE OF THE ELATERID BEETLES GLEN 23 



times also i smaller seta) at each corner; sometimes i or more tiny- 

 setae along lateral margins; a few minute pores scattered over sur- 

 face. First prementum {print I, fig. i, Z^; fig. 3, i, k) visible; pen- 

 tagonal ; usually with 3 prominent setae just caudacl to base of each 

 palpus, making transverse row of about 6 hairs ; 2 small setae poste- 

 riorly, I near each lateral margin ; 6 to 10 pores scattered over anterior 

 half of ventral surface ; anterior dorsal surface membranous, with 

 8 to 10 minute peglike "sensilla" (fig. 3, h) ; posterior dorsal aspect 

 densely clothed with branching setalike filaments (similar to filaments 

 on maxillae and hypopharynx). Second prementum (prmt II, fig. 3, i) 

 small, transverse, firmly united to first prementum ; invaginated 

 within distal end of postmentum. Labial palpi (i, 2, fig. 3, k) two- 

 jointed. Basal joint (7) cylindrical; one-half as long as prementum; 

 about as long as wide ; sometimes with 2 or 3 small, fine setae distally 

 on lateral aspect (observable only under high magnification and fre- 

 quently absent) ; about 4 pores ventrally. Terminal joint {2) small, 

 approximately one-half length and less than one-half width of basal 

 segment ; without setae ; usually with i pore ; group of minute papil- 

 lae on apex (fig. 3, /). Ligula {lig, fig. 3, i, k) reduced to small, 

 membranous, anterior protuberance and pair of forward-projecting 

 setae inserted between bases of palpi. 



Hypopharynx (hpJi, fig. 3, /; fig. 3, g) posteriorly limited by dark, 

 strong, transverse hypopharyngeal sclerome (hphsc) with ends at- 

 tached ventrally to anterior end of hypostoma by thickened mem- 

 branous bracons (lipJib) and dorsally to mesal aspect of talus by very 

 fine membranous rods (liplir) difficult to observe. Maxillulae 

 {mxitl) membranous, lobe-shaped, projecting forward with lateral 

 edges expanding ventrally ; clothed with long, fine branching seta- 

 Hke filaments (fil, fig. 3, g; fig. 4, c). Median tuft (mtit) of fila- 

 ments projects forward from between maxillulae. Anterior portion 

 of hypopharynx membranous, bearing numerous branching filaments. 



Pr coral cavity (fig. 4, d) laige, lined with membrane attached 

 dorsally to under surface of paranasal lobes and subnasale, laterally 

 to mandibles, ventrally to hypopharynx and ventral mouthparts. 

 Membrane soft and pliable except where thickened into connectives 

 supporting hypopharyngeal sclerome. Mandibles move in V-shaped 

 spaces between these membranous connectives to which they attach 

 by folded membrane. Lining of dorsal surface consists mainly of 

 transverse subnasal flap {snf, fig. 4, d; fig. 4, /) which together 

 with the sclerotization of the subnasale possibly constitutes the 

 epipharyngeal region (Hyslop and Boving, 1935, p. 52, footnote). 



