NO. II LARVAE OF THE ELATERID BEETLES GLEN I9 



Hyslop and Boving (1935, p. 55, fig. 9, a) have been followed in 

 naming the major divisions of the sternum in the thoracic segments. 

 Thus the anterior ventral sclerites are regarded as presternum; the 

 area lying between the presternum and an imaginary line joining the 

 f ureal pits (observable in prothorax at inner anterior margins of bases 

 of coxae, but not evident in mesothorax and metathorax) is desig- 

 nated eustermim; the sternellum lies behind the eusternum, between 

 the bases of the coxae, being limited posteriorly by an imaginary or 

 real line joining the posterior limits of the attachments of the coxae ; 

 the poststernellum is the extreme posterior part of the sternum, lying 

 behind the sternellum. lliis interpretation seemed best since the 

 homology of these sclerites has never been definitely established. 

 However, it is pertinent to note that in the mesothorax and meta- 

 thorax the "presternal sclerites" take a position suggestive of "inter- 

 sternites" as interpreted by Snodgrass (1935, pp. 76, 78, fig. 39 

 A, 1st). 



Hyslop and Boving (1935, p. 55, fig. 4) have also been followed 

 in naming the segments of the legs : Coxa, trochanter, femur, tibio- 

 tarsus, ungula. 



MORPHOLOGY OF THE MATURE LARVA OF LUDIUS AERIPENNIS 

 DESTRUCTOR BROWN 



Length 22 mm. ; greatest breadth about 2.75 mm. on fourth and 

 fifth abdominal segments. Fully distended larvae have measured 

 25 mm., but pupation has been recorded (Strickland, 1935, p. 521) 

 when specimens attained a length of only 17 mm. Body robust ; dorsum 

 more convex than venter; slightly to moderately depressed dorso- 

 ventrally, with large membranes on lateral aspect of thorax and 

 abdomen; subparallel, with all segments broader than long, becoming 

 narrower toward extremities ; each segment widest just caudad to 

 middle, constricted between segments. Head and ninth abdominal 

 segment of approximately equal breadth (head slightly narrower), 

 being about two-thirds to three-fourths greatest body width. Dorsum 

 brownish yellow to bright yellow (near "clay color" or brighter, 

 Ridgway, 1912), venter slightly paler; mandibles, nasale, talus, and 

 prongs of urogomphi darker; membranes white or creamy white. 

 Dorsum slightly rugose, sparsely punctulate. Median dorsal suture 

 traverses all thoracic and first 8 abdominal segments, interrupted in 

 each segment in region of longitudinally striated caudal margin. 



Head (figs. i,a, b; 2, g) prognathous ; medium-sized ; subquadrang- 

 ular, with strongly arcuate sides ; broader than long, widest across 



