NO. II LARVAE OF THE ELATERID BEETLES — GLEN I 57 



formis. Specimens examined are deposited in the Canadian national 

 collection and the Pennsylvania Agricultural Experiment Station 

 collection. 



Genus LIMONIUS Eschscholtz 

 Figures 9, cj ; 10, c; 11, a, d, g; 30-32 



In the present study, the name Limonius Eschscholtz is used in 

 the broad sense, including all species that have been placed in Pheletcs 

 Kiesenvvetter and Nothodcs LeConte. The larval morphology sug- 

 gests this procedure to be best for the present at least. Hyslop ( 1921 ) 

 has shown Pheletes to be isogenotypic with Limonius, and Van Dyke 

 (1932, p. 333) suppresses the name Nothodes, placing its lone species, 

 dubitans LeConte, in Limonius, 



Accurate specific identification of the larvae of this genus is made 

 doubly difficult because of the apparent unsettled status of the tax- 

 onomy of the adults. A thorough revision of the genus would greatly 

 assist in naming the larvae. 



Larvae of 14 species of Limonius have been studied, 12 from 

 North America and 2 from Europe. 



Dr. Van Dyke (1932, pp. 333, 360) states that with one excep- 

 tion the genus is holarctic in distribution and shows a preference 

 for valleys and more open places. The great majority of the larvae 

 studied are soil inhabiting and in North America are important pests 

 in fields and gardens. Only one species, unidentified, is known to 

 occur in decaying wood, but a few prefer moist forest litter. 



On the basis of rather scanty information it appears that pupa- 

 tion occurs most commonly in July or early August. The newly 

 developed adults pass the winter in their pupal chambers. 



Limonius is part of that large, complex group whose larvae possess 

 an undivided prosternum (prst, fig. 31, c), have impressions on the 

 mediotergites of mesothorax and metathorax, and with one excep- 

 tion, L. pilosus (Leske), have the nasale tridentate at the tip. On 

 the basis of larval characters the closest allies appear to be Elathous 

 hicolor (LeConte), Ludius resplendens (Eschscholtz), and species of 

 the Ludius limoniiformis group. 



Generic separation is greatly facilitated if Limonius larvae are 

 considered in two artificial groups: Group I, caudal notch small; 

 outer urogomphal prongs reduced to the size of small tubercles 

 (figs. 30, d, f; 31, d, e). Group II, caudal notch small; outer uro- 

 gomphal prongs at least moderately well developed (figs. 30, h; 31, f ; 

 32, d, e), sometimes as long as inner prongs; and ninth abdominal 

 segment (figs. 30, h; 32, d) without a mediodorsal groove and with 

 well-rounded "teeth" {to) on lateral aspects of dorsum. Group I is 



