164 Journal New York Entomological Society. [Vol. xm. 



ous degrees of fuscous, greenish-white and testaceous, all more or less 

 marked with black, which color, however, is sometimes absent. 

 Prof. Uhler at one time was of the opinion that the European JV. 

 glauca L. was to be found in America, basing it on the light-colored 

 unicolorous individuals that are at times to be found in the Eastern 

 United States. Individuals from mountainous regions are in general 

 somewhat stouter in form, with flattened heads and more strongly 

 arched pronotum. 



I wish here to express my gratitude to the gentlemen who have in 

 many ways most kindly helped me in this work : To Dr. L. O. 

 Howard for the privilege of working over the U. S. National Museum 

 material ; to Mr. George W. Kirkaldy for much encouragement and 

 valuable assistance in many ways ; to Professor Herbert Osborn, Mr. 

 Otto Heidemann, Mr. E. P. Van Duzee, Prof. H. T. Fernald, and 

 many other gentlemen for gifts and loans of specimens. 



In conclusion, I may say that the deficiencies of this article are 

 very evident to me. It had been planned on more extensive and 

 minute lines, but the unfortunate difficulty in obtaining material from 

 our Southern and Western States has put such work out of the ques- 

 tion for the time being. Therefore, I determined to present to ob- 

 servers such of my partial results as were in a more advanced stage, in 

 order to arouse interest and make possible the completion at some 

 later date of a genuine monograph of the entire family for the region 

 I treat of here. For the same reason, I have reproduced in extenso 

 Mr. Kirkaldy's descriptions, as they are so excellent that with them 

 the work of identification of the species is much simplified ; and also, 

 I wished to make them accessible to American workers. I trust that 

 my work will be of help to all who avail themselves of it. 



BIBLIOGRAPHY. 



1. C. J. B. Amyot and Audinet-Serville. "Hemipteres" (*• Suites a Buflbn, 



Ilistoire Naturelle des Insectes"), Paris, 1843. 



2. CARLOS BERG. " Hemiptera Argentina enumeravit speciesque novas descrip- 



sit. Anales de la Socidad Cientifica Argentina, Vol. VIII, 1879. (Reprint 

 Buenos Aires and Hamburg, 1879). 



3. Emile Blanchard. In Gay's " Historiade Chile, Zoologia," 1852. 



4. J. R. de la TORRE BUENO. " Notonectids: of the Vicinity of New York," 



Journal of the New \ r ork Entomological Society, Vol. X, No. 4, 1902. 



5. . "A Palsearctic Notonecta," Entomological News, Vol. XV, 1904. 



6. . " A List of Certain Families of Hemiptera Occurring within Seventy Miles 



