Sept., 1905.] Bueno : Notonecta of North America. 155 



eggs, which are elongated, cylindrical, and white, are attached to 

 aquatic plants." Professor Packard, in " Half Hours with Insects," 

 V, p. 159, also briefly refers to the ovum. 



I have seen one JV. undulata in the act of ovapositing, but not 

 knowing what she was doing until too late, all I noticed was an in 

 and out motion of the terminal abdominal segments, lasting possibly 

 half a minute. When she swam away, there was the pearly white 

 egg. I have frequently noted the parenchyma of the weeds slightly 

 abraded, and in the groove thus formed, the ovum is placed. 



4. Notonecta variabilis Fieber. 

 JV. varibilis. 



1S51. Fieb., Abh. Bohm. Ges. Wiss. (5), VII, p. 477 (in part). 

 1879. Berg, Ann. Soc. Cien. Arg., VIII, p. 74. (Reprint, p. 197.) 

 1897. Kirk., Tr. Ent. Soc. Lond., p. 414. 

 1902. Bueno, Journ. N. Y. Ent. Soc, vol. X, pp. 231 and 234. 



1904. Kirk., YYien. Ent. Zeit., pp. 94 and 95. 



1905. Bueno, Journ. N. Y. Ent. Soc, vol. Ill, p. 45. 

 N- undulata. 



1885. Uhl., Stand. Nat. Hist. vol. II, p. 252 (in part). 



1886. Uhl., Ch. List, p. 28. 

 X. americana. 



1899. Ashm., in Smith's Ins. N. J., p. 144. 



Description. — " Head, notocephalic lateral margins diverging curvedly from 

 the narrow base, vertex about three times as wide as synthlipsis. Pronotum, width 

 of posterior margin not quite twice as great as the length of the pronotum. Herae- 

 lytra, clear white inclining to yellowish, with a golden pubescence. xVlar nervures 

 pale golden yellow. Pedes and abdomen as in X. undulata Say." (Kirk., Rev., 

 p. 414.) 



Long., 8.2 to 10.2 mm., lat., 3.2 to 3.7 mm. 



Distribution. — My collection: Van Cortlandt Pk., Ithaca, Putnam Co., Staten 

 Island, N. Y.; Palisades, Railway, R., Westfield, and Delair, N. J.; Chestnut Hill, 

 Pa.; Lake Forest, Fourth Lake and vicinity of Chicago, Illinois; Washington, D. 

 C; Glen Echo and Bladensburg, Maryland; Montreal, Quebec; Raleigh, N. C. 

 Hatch Experiment Station Collection ; Amherst, Massachusetts ; Pennsylvania, and 

 Maryland. U. S. National Museum Collection : Lake Maxicuche, Indiana, Wis- 

 consin, Michigan, Kansas, Rhode Island. Ohio State University collection : Maine; 

 Columbus and Ashtabula, Ohio ; Cedar Bluffs and Pine Ridge, Nebraska. 



Notonecta variabilis Fieber is readily distinguishable from JV. 

 undulata by its smaller size, the largest JV. variabilis barely equalling 

 the smallest JV. undulata ; by the form being generally more slender ; 

 and by the shape of head and proportions of the notocephalon. At 

 times, one meets an individual with black fasciae somewhat resembling 

 N. undulata, but the black is less bright and the markings less clean 



