186 MODERN SYSTEM. 



Genus 142. HELOPHORUS. Leach. Elopuorus. Fuhr., Oliv., 

 Latr., Gyll. 

 Ei/es sessile : thorax transverse. 



* Thorax and elytra furrowed. 



Sp. 1. Uel. stagnalis. Hydrophilus stagnalis. Marsh. 



Inhabits ponds, floating on the surface and walking on aquatic plants. 



** Thorax and elytra with elevated lines. 

 Sp. 1. Ilel. nuhilus. Gyll. 



Genus 143. HYDllOCHUS. Germar., Leach. Elophorus. Fabr., 

 Illig., 4"C. 

 Eyes rather prominent: thorax elongated. 

 Sp. 1. Hydr. cicindeloidcs. Hydrophilus cicindeloides. Marsh. 

 Inhabits ponds, and may frequently be found in the mud at the sides. 



Stirps 2. — Clypeus entire. 



Genus 144. OCHTHEBIUS. Leaclis Edinh. Encycl.—Zool. Misc. 

 vol. iii. Elophorus. Fabr. Hydr.cna. Latr., Illig. 

 Maxillary palpi with the middle and last joint slender and acute. 

 Sp. 1. Och. riparius. Leach. Hydrophilus impressus. Marsh. 



Genus 145. HYDRvENA. Kugellan, Leach. 

 Maxillary palpi with the last joint long and acuminated. 

 S]). 1. Hyd. KugeUani. Leach. Hydro, longipalpus. Marsh, 



Fam. XX. Hydrophilid^e. 



Mandibles at their points bidentate : body oval or round : antenna ter- 

 minated by a chib. 



Stirps 1. — Clypeus emarginate : sternum simple : antemm with six ar- 

 ticulations. 



Genus 146. SPERCHEUS. Fabr., Latr., Leach. 



Sp. 1. Sper. sordidus. Spercheus sordidus. Fabr. Hydr. sordidus. 

 Marsh. 



Inhabits stagnant waters. 



Stirps 2. — Clypeus whole : sternum simple. 



A. Elytra with the apex whole. Scutellum small. 

 Genus 147. BEROSUS. LeaclCs Zool. Misc. wo\.\n. 

 Body narrow before : thorax convex : eyes rather prominent. 

 Sp. 1. Ber. Iu7'idus of authors. 

 Inhabits ponds. 



