TkE CANADIAN ENTOMOLOGIST. 225 



• Literature Cited. 

 Dolbear, A. E. 



1897. The Cricket as a Thermometer. American Natu- 

 ralist, Vol. XXXI, pp. 970-971. 



Bessey, Carl A. and Edward A. 



1898. Further Notes on Thermometer-Crickets. American 

 Naturalist, Vol. XXXII, pp. 263-264. 



Edes, Robt. T. 



1899. Relation of the Chirping of the Tree Cricket 

 {(Ecanthus niveus) to Temperature. American 

 Naturalist, Vol. XXXIII, pp. 935-938. 



Folsom, J. W. 



1906. Entomology with Reference to Its Biological and 

 Economic Aspects. P. Blakiston's Sons, Philadel- 

 phia, pp. 1-485. (p. 106.) 



TWO UNDESCRIBED WATER BUGS FROM THE UNITED 



STATES. 



BY J. R. DE LA TORRE BUENO, NEW YORK. 



If one takes up any of the authoritative text-books of entomology, 

 especially such as refer to the Eastern United States, one will find that in 

 certain of the families of the so-called Cryptocerata the Eastern American 

 species rarely exceed two or three in as many genera. Such, for instance, 

 is the case with the Nepid(t, for which only two species are given ; the 

 Gelastocoridce.^ wliich is stated to have but two or (counting Ochterus as 

 in the family) three species in as many genera. A more pertinent example 

 is the family Naucoridce, of which there is only one species known on this 

 side of the continent ; to this I add another, Pelocoris Carollnensis, miiii, 

 described hereafter. The Notonectidce have fared better, and the five thus 

 far known are increased to six for the Eastern United States. Both these 

 additions are due to the assiduous labours of Mr. C. S. Brimley, to whom 

 I am grateful for many very interesting things noted elsewhere. 

 Family Nutonectid.'r, Genus Notonecta, Linne. 



Notonecta Ra/eighi, nov. sp. =- JV. variabilis, partim, Bueno. J. N. 

 Y. Ent. Soc, xiii, p. 155. 



Head. — Notocephalic lateral margins nearly straight; vertex more than 

 six times as wide as synthlipsis ; base of eyes over four times as wide as 

 synthlipsis. 



Pronotum two-thirds broader than long ; base and lateral margins 

 nearly straight, humeral margin sinuate. Scutellum one-quarter broader 



July. 1907 



