DYTICIDJE. HYDATICUS. 85 



Sp. I. transversalis. Niger, ihorace antice lateribusqae ferrugineo, etytris vittcC 

 marginali stridque baseos subundulatd abbreviate Jlav is. (Long. corp. 6 — 6^ 

 lin.) 



Dy. transversalis. Fabricius. — Hy. transversalis. Steph. Catal. p. 51. No. 519. 



Black : head with the mouth and forehead testaceous-yellow, with two transverse 

 ferruginous spots, and sometimes a triangular one in front : thorax anteriorly 

 and with the lateral margins testaceous-yellow, the posterior edge with a hroad 

 anteriorly rounded black patch : elytra rather convex, with the margin broadly 

 yellowish, throwing off obliquely several interrupted dashes to the disc, which 

 has three punctate striae ; near the base of each elytron is a slender waved 

 pale stripe, neither touching the suture nor the marginal band : body glossy- 

 black beneath, with the apex and margins of the abdominal segments pitchy- 

 ferruginous, and the sides of the latter frequently spotted with the same: 

 legs ferruginous, the four anterior palest. Female with the thorax strigose, 

 and the tarsi simple. 



Var. /3. With the abdomen entirely ferruginous beneath. 



The transverse streak at the base of the elytra varies considerably in width, and 

 in some individuals it is broken in two. 



I once met with this species in a pond in Battersea-fields : it has 

 since been taken abundantly in Yaxley-fens by Messrs. Chant, 

 Bentley, and Weaver. " One specimen found in the pond in the 

 Botanic-garden, Cambridge." — Rev. L. Jenyns. "Pools, Netley." 

 — Rev. F. TV. Hope. 



Sp. 2. Hybneri. Niger, thorace antice lateribusqae ferrugineo, elytris vittd 



marginali Jlavd. (Long. corp. 6± — 7 lin.) 

 Dy. Hybneri. Fabricius. — Hy. Hybneri. Steph. Catal. p. 51. No. 520. 



Rather larger than the foregoing; deep black: head as in that insect: thorax 

 moderately convex, with the anterior margin narrowly yellow, the sides broadly 

 so, the base black in the middle : elytra slightly convex, glossy black, the ex- 

 terior margin broadly yellow, posteriorly irrorated with black, the disc of each 

 elytron with three striae of minute impressions, the outermost obsolete : body 

 glossy black beneath : four anterior legs pale testaceous, posterior pitchy-black. 

 Female with the thorax strigose, and the tarsi simple. 



Far less common than the last, with which it has frequently been 

 taken in company. " Whittlesea Mere." — Messrs. Bentley, Chant, 

 and Dale. " Pools, Netley."— Rev. F. W. Hope. 



Sp. 3. stagnalis. Plate XII. f. 5. — Niger, capite thoraceque antics, pedibusque 

 anterioribus luteis, elytris nigris, margine lineisque luteis. (Long. corp. 

 6— 6i lin.) 



Dy. stagnalis. Fabricius.— Hy. stagnalis. Steph. Catal. p. 51. No. 521. 



Black : head broadly yellow anteriorly, with the crown black, and bearing two 

 transverse ferruginous spots : thorax moderately convex, reddish-yellow an- 



