NO. II LARVAE OF THE ELATERID BEETLES— GLEN IO3 



This larva is readily distinguishable from rotundicollis (Say) by 

 its much paler color, relatively larger inner prongs on urogomphi {ipr, 

 fig. 21, c, d), the presence of small but definite impressions on medio- 

 tergites of mesothorax and metathorax, and the absence of a seta 

 near the center of each mediotergite of first to eighth abdominal seg- 

 ments. Sulcicollis resembles more closely the "eastern species" of 

 rotundicollis than the "western species" ; the similarity is most pro- 

 nounced in the setation, the "western" rotundicollis bearing many 

 more setae. 



Length 15 mm.; greatest breadth 2.75 mm. A fully distended 

 larva measured 21 mm. Dorsum chestnut brown, eighth and ninth 

 abdominal segments darkest ; on mediotergites of abdominal seg- 

 ments the pigmentation is slightly deeper in the regions lying within 

 the angles of the impressions. Dorsum slightly rugose, moderately to 

 densely punctate, punctures small, except on ninth abdominal segment. 



Epicranial plates with 2 pairs of large lateroepicranial setae and i 

 large seta farther dorsad, but without setae between the region of 

 the paired hairs and the setae surrounding the eye ; setae anterad to 

 dorsal sulcal setae are either minute or wanting. 



Tergites of prothorax each with from 18 to 30 setae; each medio- 

 tergite of mesothorax and metathorax bears 13 to 20 setae; and each 

 mediotergite of abdominal segments carries 9 to 16 setae. Sternum 

 of first to seventh abdominal segments divided as in rotundicollis, 

 but bearing only about 7 to 10 setae. 



Coxa of prothoracic legs with up to 12 spinelike setae on anterior 

 surface, mesothoracic and metathoracic legs with up to 20 spinelike 

 setae. 



On ninth abdominal segment, region between pleurite and caudal 

 notch without punctures and approximating one-tenth to one-eighth 

 total length of segment, exclusive of urogomphi. 



Urogomphi (fig. 21, c, d) large, separate, bifid, punctulate. Inner 

 prong {ipr) small, about one-half size of outer prong, corniform, 

 projecting mesocaudad with sharp, upturned tip; bearing 2 long setae, 

 I ventrally at base of prong, the other at junction with outer prong. 

 Outer prong {opr) large, fleshy, projecting dorsocaudad, sometimes 

 slightly laterad, terminating bluntly rounded; with i large seta on 

 anterolateral aspect near base of prong. Undivided part of uro- 

 gomphus with 2 large setae ventrally just anterad to base of outer 

 prong. 



Caudal notch {en) large, U-shaped, usually broader than long; usu- 

 ally not narrowed posteriorly. 



