154 Journal New York Entomological Society. [Voi.xin. 



Notonecta undulata Say is by far the most widely-spread species to 

 be found in America. It ranges from British Columbia down through- 

 out the continent, spreading east and south and ranging down into 

 Chile (according to Kirkaldy, Rev. Not.). The characters given 

 under the preceding species serve to distinguish it from them and from 

 N. variabilis, although small, white specimens of N. undulata may 

 be confused with the latter. Kirkaldy has proposed three color-varie- 

 ties for this bug, calling the pure white, or moonlight, color, with a 

 sienna brown dot at the base of the membrane, var. maculata ; the 

 form with black fasciae at the junction of the corium and membrane, 

 var. undulata : and the fasciated form with corium suffused with black, 

 var. charon. While these terms are somewhat useful, it is neverthe- 

 less impossible to draw a definite line between the various forms. In 

 a long series, all intergrades are to be found, from the pure white, or 

 moonlight color before mentioned, to an insect nearly all black, ex- 

 cept for a little white on the clavus and corium, and a small, nearly 

 round spot at the apex of the corium, next the membrane. There are 

 in the National Museum collection five specimens from Louisiana col- 

 lected by C. F. Baker, in which a broad black band occupies the pos- 

 terior portion of the corium and the entire membrane. I have re- 

 cently received this form from Dr. R. E. Kunze, from Phoenix, 

 Arizona. Otherwise, it is indistinguishable from the typical insect. 

 Another specimen in the same collection, from Salt Lake, Utah, while 

 having the notocephalic and pronotal structure of this species, in gen- 

 eral contour and color may be taken for Notonecta variabilis. In the 

 American Museum of Natural History, there is a specimen from Guada- 

 lajara, Mexico, which is practically entirely black, varying in tone 

 from deep velvety to brownish black, where in typical specimens the 

 white markings are. 



As previously mentioned, this is the most common species of 

 America and easily obtainable at all times. I have endeavored to 

 breed it but have not succeeded in carrying it beyond the second 

 or third instar, owing to the lack of proper food. However, having 

 obtained a number of ova, I give the following description : 



Ovum. — Length, 1. 9 to 2 mm. Clear glistening pearly white when recently 

 deposited. Chorion sculptured in irregular hexagons. Shape, elongatr 



The only other descriptions known to me are a brief note by 

 Prof. H. Carman in Bulletin Illinois State Laboratory of Natural His- 

 tory, Vol. Ill, where on page 174 he says the following: "The 



