226 
MODERN SYSTEM. 
Fam. VII. NoTOXECTrD.E. Leach. 
“ Linne and all his predecessors comprehended the species under 
the generic appellation Notonecta. The accurate Geoffroy was the 
first who separated Notonecta into two genera, which have been 
adopted by most succeeding writers, excepting Linne, who in his 
last edition of the Syslcma Nature has merely given the synonym 5 
of that author, without taking the least notice of the important cha- 
racters which induced hitn to separate them.” 
Do Geer confounded the animals of this tribe with Nepa. and Nau- 
coris, whilst Latreillc and Olivier placed them in a division of their 
family Hydrocorisa. In the Edinburgh Encyclopedia Dr. Leach se- 
parated them front the Hydrocoriste, and placed them in a particular 
tribe, named in that work Notonectidcs, and in the twelfth volume ot 
the Transactions of the Linnean Society he has given an excellent pa- 
per, in which are described at large the whole of the British species 
hitherto discovered, which consist of four very natural genera. 
Stirps 1. — Body cylindrical oval, or nearly square: tarsi with two arti- 
culations. ( Scutellum large.) 
“All the insects of this family swim on their back, moving by means 
of their long hinder legs, which resemble oars ; whence they have 
been aptly named boat-flies.” 
Genus 289. NOTONECTA of authors. 
Body oval and cylindric: antenna with the third articulation slenderer 
than the second: anterior tarsi with the first articulation long : chocs 
of the hinder feet very minute. 
Besides the above characters, the following will be useful, in order 
to enable the young entomologist to distinguish this genus from 
Flea, from which it was first separated by that close examiner ot 
nature Dr. Leach. 
The thorax is hexagonal ; the anterior part is much attenuated; 
aud the hinder margin is straight: the head is narrower than the 
broadest part of the thorax : the eyes are oblong, and converge a lit' 
tie behind : the hinder legs are much ciliated, and the claws are so mi' 
nute as to be discovered with great difficulty; the tips of the elfl ra 
are notched. 
Sp. 1. Not.furcala. Elytra black, with two grayish spots at the hasty 
and two larger ones at the posterior part. 
Notonecta furcata. Fabr., Otiv., Leach. 
Var. (3. Elytra with ferrugineous spots. 
Inhabits ponds and ditches in England and Scotland. 
Sp. 2. Not. maculata. Elytra dark brown and varied with spots : back 
ferrugineous with a darker fascia. 
Notonecta maculata. Oliv., Leach. Notonecta glauca. Var. /3. Latr. 
