NO. II LARVAE OF THE ELATERID BEETLES GLEN 49 



than ill acripeniiis destructor (fig. 6, a, c) and on the ninth ab- 

 dominal segment continuing clearly across the dorsum ; subnasale worn 

 on specimens examined, but giving indications of about 12 denticles 

 on the serrate ridge. The material examined showed no distinct color 

 differences from aeneus. Somewhat larger tubercles, as indicated by 

 Znamensky, undoubtedly occur in specimens entirely free from ero- 

 sion, but this character is believed to be very variable and should be 

 used only to supplement the characters given above. 



Material used in study. — ^Three larvae were examined. All were 

 collected at Chuchkova, Moscow District, Russia, 1936, and were 

 identified by M. Ghilarov. It is not known if the identification was 

 supported by rearing. (U. S. National Museum collection.) 



THE LUDIUS INFLATUS GROUP 

 Figures 13, /, h; 16, a 



KEY TO SPECIES 



I. Transverse branches of impressions on the mediotergites of second to 

 eighth abdominal segments reaching from one-eighth to one-sixth of 

 the distance from longitudinal branches to mediodorsal suture; 



western North America glaucus (Germar) (p. 50) 



Transverse branches of impressions reaching from one-fifth to one-fourth 



of distance to dorsal suture ; eastern North America 



inflatus (Say) (?) (p. 55) 



Knowledge of this group is based upon the larva of glaucus 

 (Germar) and specimens from Urbana, III, which are probably in- 

 flatus (Say). Both species are soil inhabiting; their larvae have been 

 confused and commonly referred to in the economic literature under 

 the one name, inflatus. 



This group is very closely allied to the oeripennis group, differing 

 as follows: caudal notch subcircular or subovate; urogomphi and 

 prongs relatively longer and more slender, bearing larger toothlike 

 tubercles; ninth abdominal segment with 2 or 3 sharp "teeth" on 

 lateral margins of dorsum, without setae on central dorsal area, and 

 distance between pleural area and caudal notch equal to one-fifth to 

 one-fourth length of segment exclusive of urogomphi; 3 latero- 

 epicranial setae on each gena, arranged as i pair with an unpaired 

 hair farther ventrad; without definite impressions on mediotergites 

 of mesothorax and metathorax. 



