98 MANDIBULATA. — COLEOPTERA. 



Gy. tricolor. Fabricius. — Curtis, ii. pi. 79. — Steph. Catal. p. 54. No. 542. 



Elongate, subcylindric, very smooth blue-black: head, thorax, and scutellum 

 exactly as in Gy. natator : elytra very much elongated, and slightly attenuated 

 posteriorly; the disc very finely punctate-striate, and of a deep blue-black, 

 with the margins aeneous, the inflexed one ferruginous : middle of the breast 

 ferruginous ; abdomen beneath blackish-brass, with the apex of the last segment 

 pitchy : legs rufo-testaceous. Female rather broader, and longer in proportion 

 than the male. 



Not common ; found in Norfolk and Suffolk. " Near Southend, 

 and at Tenbury, Worcestershire." — Rev. F. W. Hope. " Salt 

 marshes and lakes in Devonshire, during the spring." — Dr. Leach. 



B. Elytra villose, punctate. 



Sp. 8. villosus. Oblongus, supra niger, griseo-pubescens, subtus Jlavus , elytris 



vage punctatis. (Long. corp. 2§ — 3j lin.) 

 Gy. villosus. Illiger. — Steph. Catal. p. 54. No. 543. 



Oblong, convex, subfusiform ; above dusky-black, rather glossy, and thickly 

 clothed with a short grayish down: head finely punctulated, a little brassy; 

 the margin of the labrum with elongate pale cilia : thorax very convex, faintly 

 punctulated, and slightly tinted with aeneous : elytra elongate, very convex, 

 arched, covering the abdomen, above thickly punctate, the lateral margin pale 

 rufescent : the body testaceous-yellow beneath, the abdomen frequently yellow, 

 the terminal segment narrow, conic, with a tuft at the apex : legs pale : an- 

 tennae pale at the base and apex, with the intermediate parts pitchy-black. 



This species generally frequents rivers and running water, but 

 is rare near London. " Common on the Dart, and in rivulets on 

 Dartmoor." — Dr. Leach. " Netley, rare." — Rev. F. W. Hope. 

 " Slap ton Ley, in June last." — Mr. Chant. 



Section II. — Rypophaga, 



Or Cleansers, may be characterized by having four palpi only, two labial and 

 two maxillary; the internal maxillary being represented, according to the 

 analytical views of Mr. Mac Leay, by the external lobe of the maxilla, which 

 is generally dilated, and frequently articulated, though rarely palpiform : the 

 antenna clavate, or gradually thickening from the base to the apex. 



This section, following the views of the last-named writer, is 

 divisible into three others ; of which the first that presents itself is 



Subsection 3.— Philhydrida, Mac Leay, 



Or such insects as have the mandibles rarely exserted : the maxillary palpi usually 

 four-jointed: the maxilla? with the outer lobe generally articulated: the elytra 

 covering the abdomen: the body mostly short, convex, or rounded on the 



