4530 Insects. 



capture a distinct and cumbersome apparatus ; there appears among 

 them but little variety of form ; and the species known to be 

 indigenous are few and often local : nevertheless, a study of their 

 economy well rewards the naturalist; their habits and metamor- 

 phoses are as interesting as they are little known ; while the assumed 

 limited number of native species encourages the hope that an 

 acquaintance with all is not impossible. 



During the last two years I have paid some attention to these 

 groups; and, with the object of inviting the attention of others, send 

 you some memoranda respecting their localities and captures. I 

 should state that the nomenclature I adopt is that of Dr. Schaum, at 

 p. 1887 of your magazine. 



Haliplus elevatus. Sparingly in the reservoir near Daventry. 



„ mucronatus, StepJt. Two specimens in Holme Fen, Hunt- 

 ingdonshire, 1853. This appears to be either a very local or a rare 

 insect with us; though Dr. Aube has taken it very abundantly in the 

 neighbourhood of Compiegne. 



„ fulvus, Fab. Not uncommon. 

 Chemidotus csesus. Common in the neighbourhood of Whittlesea 

 Mere in June. 



Hydroporus decoratus, Gyll. I took a few specimens of this insect 

 in Horning Fen, Norfolk, in a ditch densely covered with duck-weed. 



„ confluens, Fab. Very sparingly at Holme Fen. I 



have never met with this species (common, according to Stephens) in 

 any abundance. 



„ Davisii, Cart. Near Norwich, in a small gravelly 



brook. May, 1854. 



„ assimilis, Payk. In the utmost profusion in the lake 



near Kean's Cottage, Isle of Bute, September, 1854; also near 

 Northampton, August, 1853. 



„ halensis, Fab. Five specimens, as the result of three 



days' hard work, in a lake near Loch Spelvie, Isle of Mull, 

 September, 1854. 



„ elegans, III. A dark variety of this species common 



in the Isle of Bute, September 1854. 



„ parallelogrammus, Ahrens. In profusion near Sheer- 



ness. 



„ 9-lineatus, Rudd. In lake near Kean's Cottage, Isle 



of Bute, September, 1854. Not common. 



„ vittula, Erichs. Sparingly in the neighbourhood of 



Norwich, May, 1851. 



