NO. II LARVAE OF THE ELATERID BEETLES GLEN I5I 



becoming narrower in more posterior segments ; sternum undivided ; 

 and spiracles in anterior half of each segment. 



LUDIUS LIMONIIFORMIS (Horn) (?) 



Figures ii, h; 29, a-c 



Corymbites limoniifonnis Horn, Trans. Amer. Ent. Soc, vol. 3, p. 320, 1871. 

 Ludius limoniiformis (Horn), Van Dyke, Proc. California Acad. Sci., vol. 20, 

 p. 420, 1932. 



According to Van Dyke (1932, pp. 396, 420) this species "seems to 

 be rather widely spread in the country to the west of the Great 

 Lakes," and apparently extending into Alberta. 



The larvae are known from the parklands of Saskatchewan, where 

 they are found most frequently in association with the grassy margins 

 of snowberry {Symphoricarpos) and silverberry (Elaeagnns) thickets. 

 The species persists for many years after such areas are brought under 

 cultivation. King (1928, p. 705) refers to L. limoniiformis as a crop 

 pest of minor importance in Saskatchewan. 



This larva resembles the more eastern cylindrifonnis (Herbst) but 

 is smaller, and has more "teeth" on the margins of the dorsum of the 

 ninth abdominal segment (fig. 29, b). 



Description of "mature" larva. — Length 16.5 mm. ; greatest breadth 

 2.0 mm. ; thoracic and abdominal segments subequal in width with 

 prothorax sometimes widest segment. Fully distended larva measured 

 22 mm. Body only moderately robust ; with moderate-sized mem- 

 branous areas on lateral aspect ; most segments of abdomen as long 

 as wide ; head and ninth abdominal segment about five-sixths greatest 

 body width. Dorsum light brown to yellowish brown (near "clay 

 color," Ridgway, 1912) ; head and prothorax distinctly darker; venter 

 slightly paler. Dorsum slightly rugose, more pronounced rugosity on 

 abdomen ; with sparse small punctures, more abundant on more poste- 

 rior segments. 



Head subquadrangular with arcuate sides ; flattened above and 

 below. 



Frontoclypeal region with posterior part extending backward almost 

 to foramen magnum ; truncate posteriorly. Two prominent anterior 

 nasosulcal setae on each side of base of nasale. Nasale {n, fig. 29, a) 

 a well-developed tooth terminating tridentate when uneroded ; median 

 denticle large, small lateral denticles frequently eroded giving appear- 

 ance of unidentate tip. Subnasale {sn) consists of many fine, short, 

 sharp, forward-projecting denticles ; frequently eroded. Paranasal 



