Notonecta maculata.Oliv. Encycl. Méthod. Hist. Nat. viii. 388. 4.
Notonecta glauca var. A.Latr. Gen. Crust. et Ins. iii. 150.
Habitat in Angliâ prope Bristol, Plymouth, et Exeter.
Elytra apice fuliginosa.
Spec. 3. Notonecta glauca.
N.elytris griseis margine fusco-punctatis, dorso nigro apice pallido.
Notonecta glauca auctorum.
Var. β. Elytris subferrugineis fusco-subirroratis.
Var. γ. Elytris apice subnebulosis.
Var. δ. Elytris pallidis itnrnaculatis.
Habitat in Britannia vulgatissime.
This species is by far the most common that occurs in Great Britain. The back of the abdomen is always black, terminated with pale yellow. Var. β at first sight bears a near resemblance to N. maculata; but the spots in the front of the elytra, and the colour of the back, will readily distinguish them. Var. γ I twice received from Mr. S. W. Millard, who took them near Bristol. Var. δ I found in the north of England, and I suspect it to be an immature specimen. All the varieties, excepting the last, have a small blackish spot on the hinder margin of the elytra; but it is much more distinct in some specimens than in others, and it is never to be seen in N. maculata: this affords another character for discrimination, and therefore ought not to remain unnoticed.
Gen. 2. Plea.
The thorax is obscurely hexagonal, with the hinder margin prominent and rounded; the head as broad as the broadest part of the thorax; the eyes are rather oblong, without the least tendency to converge behind; the hinder pair of legs not more ciliated than the others, but are terminated by very strong and distinct claws; tips of the elytra acuminated and entire.
