HYDROPHILIDjE. — HYDROBIUS. 129 



b. Elytra with one stria at the suture, or plain. 

 Sp. 5. melanocephalus. Ovatus, niger, thorace pallido, disco ni^ro, elytris pal- 



lidis, stria suturali impressd. (Long. corp. 2 — 3 lin.) 

 Hy. melanocephalus. Fabricius. — S'eph. Catal. p. 60. No. 607. 



Ovate, black ; finely punctured : head punctulated, black, with a pale marginal 

 lunule before each eye : thorax finely and thickly punctured, pale griseous- 

 testaceous, with a discoidal and two contiguous spots black: elytra oblong, 

 pale griseous, with a dusky humeral spot, and a deep stria parallel with the 

 suture : body dull black beneath, pubescent : legs pale ferruginous ; femora 

 generally pitchy-black. 



Var. jS. Rather larger, with the thorax obsoletely spotted with dusky; the crown 

 darker, and frequently a longitudinal fuscous stria on the forehead. 



Var. y. Steph. Catal. 1. c. With the head immaculate black ; the thorax with its 

 disc black ; its margins and the elytra castaneous-red. 



Plentiful in Battersea-nelds during April and the beginning of 

 May; and far from uncommon in other places round London at the 

 same season, and in Norfolk. "Bottisliam, not common." — Rev. 

 L. Jenyns. " Southend." — Rev. F. W. Hope. 



Sp. 6. torquatus. Supra griseo-testaceus, vertice thoracisque disco obsoletius 

 infuscatis, elytris subtilius punctulatis, stria suturali profundi impressd. 

 (Long. corp. 2§ — 3j lin.) 



Hy. torquatus. Marsham. — Hy. melanocephalus £. Steph. Catal. p. 60. No. 607. 



Much larger than the last, the colour paler, less glossy, the punctures on the 

 thorax and elytra smaller in proportion, &c. Above griseous-testaceous ; head 

 more or less clouded with fuscous : thorax with an obsolete brown cloud in 

 the middle : elytra rather paler, very finely punctulated, with a deep stria on 

 each near the suture, sometimes sprinkled with blackish dots towards the base, 

 the apex generally immaculate : body punctulated beneath and black : femora 

 at the base and beneath black ; the apex above with the tibiae and tarsi pale 

 testaceous. This is the Hydrophilus grisescens of Gyllenhal, which I con- 

 ceived might be a variety of the foregoing insect when my Catalogue was 

 printed. I am now of a different opinion. 



Found near Hertford and Ripley in the spring. 



Sp. 7. testaceus. Ovatus testaceus, vertice corporeque nigris, pedibus pallidis, 



elytris strid suturali impressd. (Long. corp. "2± lin.) 

 Hy. testaceus. Fabricius. Steph. Catal. p. 60. No. 608. 



Closely allied to the foregoing, of which it may possibly prove to be a variety : 

 rather smaller : the body beneath dull black ; the crown glossy-black ; the 

 head anteriorly, thorax, and elytra immaculate testaceous ; the legs pale; the 

 upper surface very finely and thickly punctulate. 



Taken occasionally near London in the spring. 



Mandibulata. Vol. II. 1st February, 1829. k 



