82 



SERRICOBNIA. 



[Elateridce. 



1. Margin of the front elevated behind the lahrum ; 



size smaller. 



A. Prostcrual spine truncate behind ; scntellura 

 conlifonn ; larv.i with the abdominal segments 

 widi-ly separated by mcmbrnnous divisions . . 



B. Prosternal spine acute ; scutellum oval ; lurva, 



ns a rule, with the abdominal segments ap- 

 proximate. 



a. Posterior angles of thorax spiniform; pro- 

 Bteriinm broad, with sutures single .... 



b. Posterior angles of thorax produced, but not 

 ppiniform ; prosternum moderate, with su- 

 tures double. 



a*. Prosternal sutures excavated in front ; 



second joint of antennas shorter than third 



b*. Prosterntil sutures not excavated in front. 



af- Antennas strongly serrate, with the 



second joint much shorter than third . 

 b+. Antenna) more feebly serrate, with the 

 second joint about equal to third . . . 



2. Margin of the front not elevated behind the 

 labrum ; second and third joints of antenna) very 

 short 



ii. Coxal plates gradually dilated inwards. 



1. Elytra without ventral epipleurae ; eyes more or 



less sunk in thorax. 



A. Front not convex ; mouth not inferior ; * an- 



tenna? with the first joint not elongate. 



a. Claws serrate 



b. Claws simple. 



a*. Tarsi with the first joint elongate . . . 

 b*. Tarsi with the first joint not or only 

 slightly longer than second. 



af- Thorax with posterior angles short, not 

 overlapping the shoulders of elytra ; 

 anterior coxal cavities narrowly open 

 behind 



bf. Thorax with posterior angles long, over- 

 lapping the shoulders of elytra ; anterior 

 coxal cavities broadly open behind . . 



B. Front convex ; mouth inferior ; antenna; with 



the first joint elongate, forming a scape. 



a. Claws pectinate. 



a*. Tarsi with the fourth joint strongly lobed 



beneath ; thorax longer ; size much larger 

 b*. Tarsi with the fourth joint not lobed ; 



thorax shorter ; size very small .... 



b. Claws simple. 



a*. Sides of thorax obtuse, margin deflexed 



in front ; second joint of antenna? longer 



than third 



b*. Sides of thorax acute, margin straight in 



front; second joint of antenna) equal to 



third 



2. Elytra with the ventral cpipleuroj narrow but 



In Sericosomus the mouth is deflexed and almost inferior; the genus must 

 therefore be regarded as an exception. 



CABDIOPHOUUS, ZWA. 



CttVPTOHTPNUs!, Each. 



ELATEB, L. 



ISCHNODKS, Qerm. 

 MEGAPENTHKS, Kies. 



LUDIUS, Lair. 



MELANOTUS, Esch. 

 ATHOUS, Esch. 



LIMONIUS, Esch. 

 SEBICOSOMUS, Bedt. 



STNAPTUS, Esch. 

 ADBASTOS, Esch. 



AGBIOTES, Esch. 

 DOLOPITJS, Esch. 



