80 CONTRIBUTIONS TO CANADIAN PALEONTOLOGY. 



eralis Aub^, which, of our living species, it appears most to resemble, 

 and with which it agrees well in size and proportions. Length, 3°™. 



One specimen : No. 16902, Logan's brickyard, Toronto. 

 ff. humeralia is found in Alaska. 



Hydroporus sectus sp. nov. 

 PI. X., Fig. 1. 



Two slender elytra, only one of which is perfect, represent a species of 

 Hydroporus allied to H. ohlongus Steph. The punctuation is delicate and 

 rather dense (hardly shown as dense enough in our figure) and pronounced, 

 and there is an obscure margination to the outer border. It is smaller 

 than the modern species with which it is compared, and has a somewhat 

 ■denser punctuation. Length 3-8 '°", 



Two specimens : No. 16904, Reservoir Park, Toronto; No. 16905, 

 Scarborough. 



H. ohlongus occurs in Europe and also in this country in Canada, Lake 

 Superior, Michigan, and Vancouver Island. 



Agabus perditus sp. nov. 

 PI. IX., Fig. 5. 



There are preserved two fragments of what appear to be the same 

 species, referable to Agabus, one showing the basal half, the other the 

 epical two-thirds of elytra, both showing a black surface which is micro- 

 scopically rugulose (seal cely appreciable under a strong hand lens), with 

 widely scattered obscure puncta and a marginate outer border ; the hum- 

 erus is square. It appears to be nearly related to A. seriatus Say, but it 

 is wholly without the series of approximated punctures found in that 

 species. The length of the basal fragment is 3-35"", that of the apical 

 5"™ ; the probable length of the whole elytron perhaps T-S""" 



Two specimens : Nos. 16898, 16906, Scarborough. 



A. seriatus is found in Massachusetts, Pennsylvania, Colorado, Lake 

 ■Superior and Canada. 



Gyeinidae. 



Gyrinus confinis LeC. 



PI. X., Fig. 5. 



Gyrinus confinis LeC, Proc. Acad. Nat. Sc. Philad., 1868, 368. 

 A single complete elytron of flattened, tapering, round-tipped form, a 

 heavy sutural stria, distinctly marginate outer border, and with eleven 



