NO. II LARVAE OF THE ELATERID BEETLES GLEN I33 



lar to the larva of Corymhites pectinicornis except in a few respects ; 

 however, in many cases it is very difficult to separate the two larvae 

 with certainty. In the pectinicornis larva the hind portions of the 

 abdominal segments are smoother, with only very small, sparse punc- 

 tures ; the inner prongs of the cerci [urogomphi] are directed more 

 posteriorly making the angle between the two prongs more acute than 

 in aeruginosus, almost right-angled, in aeruginosus more obtuse. 

 The larva of pectinicornis has, on the hind margins of the inner prongs, 

 only a very small, almost indiscernible tubercle, in the larva of aerugi- 

 nosus the tubercle is usually somewhat larger and broader." 



In the present study, similar differences were observed in individual 

 cases, but these characters were found to vary and to intergrade so 

 much that no reliance could be placed upon them as specific characters. 



Material used in study. — Eight larvae, six from Denmark and two 

 from Finland (Suomi), were examined. These specimens formed 

 part of the material available to Henriksen ( 191 1 ) and Saalas ( 1923a) 

 in their studies on this species. To the writer's knowledge, none of 

 the material was associated with reared specimens. The larvae ex- 

 amined are deposited in the Canadian national collection, the Royal 

 Veterinary and Agricultural College, Copenhagen, and the U. S. 

 National Museum. 



LUDIUS VIRENS (Schrank) 



Elater virens Schrank, Schriften Berlinischen Gesell. naturf. Freunde, vol. 2, 



p. 317, 1781. 

 Elater aeneicollis Olivier, Journ. Hist. Nat., vol. i, p. 264, 1792. 

 Corymbites znrcns (Schrank), Harold, Coleopteralogische Hefte, vol. 5, p. 92, 



1869. — ScHENKLiNG, Colcopt. Cat. (cd. Junk), vol. 2, pt. 88, p. 363, 1927. 



Larvae of this central European species were not available for 

 examination in the present study and the remarks that follow are 

 adapted from the writings of Beling (1883, pp. 265-268; 1884, 

 p. 208), who described the larva under the name aeneicollis Olivier. 



Larvae, apparently identified through rearing, were collected by 

 Beling from moist soil under moss in the forests of Germany, beech 

 and pine forests being mentioned specifically. According to his ob- 

 servations the larvae were confined to areas covered by deposits of 

 century-old ore slag. Such areas were kept moist by nearby springs, 

 but, as a rule, the vegetation was limited to mosses and a few char- 

 acteristic flowering plants. 



Ludius virens is readily separated from the other known larvae of 

 the cupreus group by having the outer prongs of the urogomphi at 

 least twice as long as the inner prongs. It also attains a greater length, 

 reaching 30 mm. ; width 3 mm. Dorsum very dark brown (black- 



