Page:Transactions of the Linnean Society of London, Volume 12.djvu/31

Rh Notonecta minutissima.

''Linn. Fn. Sv.'' 244. 905.

''Syst. Nat.'' i. 713. 3.

Habitat in rivis, lacubus vulgatissime.

Long. Corp. 1 lin.

Linné has described this species so minutely as to leave no doubt with respect to the above reference; in the twelfth edition of his Systema Naturæ, and in the last edition of his Fauna Suecica, he has given the following characters: "N. elytris cinereis; muculis fuscis longitudinalibus. Magnitude minima arenulæ; depressa est. Pedes posteriores longiores; primum par minimum. Habet alas, elytra, scutellum."

Sigara minutissima is found in every part of Great Britain; I have observed it in the Lake of Killarney, and in other lakes in the south of Ireland; in the north of England, near Carlisle, and in Derwentwater; in Loch Lomond and Loch Katerine in Scotland; in the river Tavy in Devon; and I have frequently received it from the Norfolk collectors: whence we may infer that it occurs in that country.

To this genus probably belongs the Sigara coleoptrata of Panzer, ''Faun. Ins. Germ. In.'' 50. 24.

The thorax is more or less produced behind in all the species of this genus; but it is not evident in the first division of the genus until the elytra have been elevated. The front, the underparts of the body, and the legs, in all the British species, are yellowish.

The channel on the anterior margin of the elytra in this division is uninterrupted, and gradually disappears before it reaches to the extremity of the elytra.

Rh