226 ' MODERN SYSTEM. 



Fam. VII. NoTONECTiD^. Lerich. 



" Linne and all his predecessors comprehended the species under 

 the generic appellation Notonecta. The accurate GeoftVoy 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 Systema Natune has merely given the sjiionyms 

 of that author, without taking the least notice of the important cha- 

 racters which induced him to separate them." 



De Geer confounded the animals of this tribe with Nepa and Nau- 

 coris, whilst Latreille and Olivier placed them in a division of their 

 family Hydrocoriso'.. In the Edinburgh Encychpadia Dr. Leach se- 

 parated them from the Hydrocoriste, and placed them in a particular 

 tribe, named in that work Notonectides, and in the t^velfth volume of 

 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 \. — Borfj/ 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-Jiies." 



Genus 289. NOTONECTA of authors. 



Body oval and cylindric : antemia: with the third articulation slenderer 

 than the second : anterior tarsi with the first articulation long : ckncs 

 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 trom 

 Plea, from which it was first separated by that close examiner of 

 nature Dr. Leach. 



The thorax is hexagonal ; the anterior part is much attenuated, 

 and the hinder margin is straight : the head is narrower than the 

 broadest part of the thorax : the eyes are oblong, and converge a lit- 

 tle behind : the kinder legs arc much ciliated, and the claws are so mi- 

 imtc as to be discovered with great difficulty: the tips of the elytra 

 are notched. 



Sp. 1. Not.furcata. Elytra black, with two grayish spots at the base, 

 and two larger ones at the posterior part. 



Notonecta furcata. Fair., Oliv., 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. Xfi/r. 



