NORTHUMBERLAND AND DURHAM. 63 
16. H. puanus, Fab. 
Boisd. et Lacord. Faun. Ent. Paris., 1., 332, 10.—Heer. Fn. 
Ool. Helw., i., 155, 12.—Hyphydrus planus, Gyll. Ins. Suec., 
i, 531.—Hydroporus ater, Forst., Steph. Illust. Mand., 
i., 61.—H. holosericeus, Marsh., [b., 11., 61.—H. pubes- 
cens, /b., i1., 61.—H. fuscatus, 76., 11., 62. 
Common. 
For the synonymes we are indebted to the valuable paper of 
Dr. Schaum, Zoologist, ubi sup. 
17. H. rivaus, Giyll. 
Schaum Zoologist, 1890.—Hygrotus fluviatilis, Leach, Steph. 
Lllust. Mand., ii., 46., pl. xi., f. 2. 
In gravelly brooks, common. “ Meldon Park.”—G. Wales, 
Esq. Ouseburn, Boldon, Ravensworth, and in the Derwent. 
April—August. 
18. H. conFiugns, Fab. 
Dytiscus confluens, Fab. Syst. #1. i., 270.—Hygrotus con- 
fluens, Steph. Illust. Mand., ii., 47. 
In ponds, common. “ Newcastle."—G Wailes, Hsq. Long 
Benton, Gateshead, Ravensworth, Marsden, Black Fell. March 
—July. 
19. H. rericunatus, Lab. 
Heer. Fn. Col. Helv., i., 161, 32.—Dytiscus reticulatus, 
Fab. Syst. El., 1., 270.—Hygrotus collaris, Steph. Iilust. 
Mand., i., 47. 
Long Benton, and common at Prestwick Car, in May.— 
Me dh, 15% 
20. H. inmeuaris, Mab. 
Heer. F'n. Col. Helv., i., 160, 31.—Dytiscus ineequalis, /ab. 
Syst. Hl. i., 272.—Hygrotus inequalis, Steph. Lllust. 
Mand., i1., 48. 
In ponds and brooks, common. 
21. H. Leprpus, Oliv. 
Boisd. et Lacord. Faun. Ent. Paris., i., 336, 20.—Hygrotus 
scitulus, Spence, Steph. Illust. Mand., 1., 49, pl. xi. f. 3. 
Ponds ,and slow running streams, common. “ T'wizell.”-—P. 
J. Selby, Esq. Prestwick Car, Ouseburn, Marsden, Boldon 
Flats, Black Fell. All the year. 
