158 MODEKX SYSTEM. 



* Body elongattd. 

 Sp. 1. Hvp. l^-pushtlatus. 

 Inhabits ponda and ditches. 



** Body oral. 



Sp. 1. Hyp. conjtutns. 



D%tiscu5 contiuens. Marshnm. 



Inhabits ponds and ditches. 



Stikps 5. — ^All the tarsi with five articulations. 



Genus 58. NOTERUS. Cluh-., Latr., Leach. 

 Antenruz with a fifth or seventii joint dilated : hinder feet but slightly 



adapted for swimming. 

 Sp. 1. Hot. Geerii. Oval, convex, brown: head and thorax ferrugine- 



GU3 : el\"tra sprinkled with impressed dots : antenns of the male 



thick. 

 D^tiscus crassicomis ofattthors. D\"tis clavicornis. De Geer. 

 Inhabits stagnant waters. 



Sp. 2. Abf. sparsus. Eh-tra with impressed dots. 

 Dytiscus sparsus. Marsh., i. 430. 

 Inhabits stagnant waters near London. 



Genus 59. L^CCOPHILUS. Leach, Edin. Encycl vol. ix. 

 Antenna with the joints simple : hinder Jeet well adapted tor swim- 



rning. 

 Sp. 1. Lac. hyalmus. 

 Inhabits canals and slowly running waters. 



Sp. 2. Lac. minutus. Greenish-testaceous : legs yellowish. 

 Dvtiscus minutus. Linni, Marsh., Gyll. 

 Inhabits stagnant waters. 



C. With a scutellum : hinder feet compressed and Jormedjbr suim- 

 ming: all the tarsi with five articulations. 



Stirps 6. — Tibiiz posterior elongated : claws on the hinder feet didac- 

 tyle. 



Genus 60. COLYilBETES. ClairriUe, Latr., Leach. 

 Ejfernal maxillary palpi with tlie second and diird joint equal; fourth 



long, obtuse at the apex. 

 Sp. 1. Col. striatus. 

 Inhabits stagnant waters. 

 Sp. 2. Col. maculacus. (P/, 3. fg. 15.) 

 Inhabits ditches. 



Genus 61. n\T)ATICUS. Leach, Edinh. Encycl. vol. is. 

 External maxillary palpi with the second joint short, third and fourth 

 long bat equal and subulated: anterior tarsi of the male patellitbnn; 

 female with the thorax rough on buth sides ; elytra smooth. 



