NEW BRITISH SPECIES, ETC., IN 1869. 51 



13. Hydroporus derelictus, Clark; Ent. Ann., 1863, 



71 ; Schaum, 1. c, 61 ; Gemminger and v. Harold, 

 Cat. Col. ii; E. C. Rye, Ent. Mo. Mag., v, 248; 

 D. Sharp, 1. c, 85. 

 This insect (described from the Orkneys) seems unani- 

 mously referred to erythrocephaluSj Linn. ; but I admit my 

 present inability to reconcile the example in Dv. Power's 

 possession with that species. It must be, at all events, an 

 extremely aberrant form. Dr. Schaum states it to be only 

 somewhat larger than the type. 



14. Agabus Erichsoni, Gemm. and v. H., 1. c; E. C. 



Rye, 1. c. 



nigro-cEneuSf Er., nee Marsham. 

 My proposition to confer this name on Erichson's- nigro- 

 ceneus (Ent. Ann., 1869, p. 16,) is anticipated by Gem- 

 minger and V. Harold. 



15. Agabus tarsatus, Zetterstedt, Ins. Lapp., 152, 25; 



Thomson, Sk. Col., ii, 64; Schaum, 1. c, 

 100; D. Sharp, 1. c, 85. 

 melanariusj Aube. 

 Widely distributed in the northern parts of Europe, but 

 everywhere scarce. A single specimen is in Dr. Power's 

 collection, taken, as Dr. Sharp believes, by Mr. Syme, in 

 the Orkneys. 



The insect is allied to A. striolatus (having the upper sur- 

 face covered with fine irregularly anastomosing striae), and 

 differs from that species in its regularly oval form, the less 

 longitudinal disposition of the above-mentioned striae on its 

 elytra, and in having an obscure pale dash at the side of each 

 elytron near the apex. 



e2 



