TANUARY 2^ 



INYERTEBRATA PACIFICA 



Edited by C. F. Baker, Estacion Agronomica, Santiago de las Vegas, Cuba 



HEITEIRORTEIRA 



NOTES ON THE NYSIUS AND OETHOLOMUS OF AMERICA 

 C. F. BAKER 



Many years ago when first collecting Nysiuit — a genus of true bugs often 

 very injurious to certain cruciferous plants, beets, etc., but also occu- 

 rring on many other plants — all attempts to arrange the species in my 

 collection according to the original descriptions were attended by unsa- 

 tisfactory and discouraging results. Had I been a collector of few spe- 

 cimens it might have been possible but I very early acquired the habit 

 of taking large series, and the farther I carried such work, the more 

 surely was the absolute necessity for it recognized. This is equally 

 true among all animals and plants, but Nijuim^ has proven an unusually 

 pointed example of it. I have now before me twelve hundred spec- 

 imens belonging to my two collections, (one in National Museum and 

 one here in Cuba) which have been taken in Colorado, Arizona, New 

 Mexico, Nevada, California, Nicaragua, Oregon, Washington, Alabama, 

 Cuba, and the Eastern United States. The variation in coloration among 

 the individuals of the different species is something altogether remar- 

 kable, the general pattern being much the same in all, apparent diffe- 

 rences in the majority of cases being due to varying intensity of pig- 

 mentation. This fact renders most of the original descriptions of American 

 species almost useless. In two late description (those of movticola and 

 ementilus) , scarcely a single structural character is given, not even the 

 primary ones of amount of curvature of costal margin of corium, and 

 form of bucculae. 



After careful studies in the comparative anatomy of the various 

 species were begun, many good characters were found which had not 

 been mentioned by any of the authors. Others which had been mentio;. 

 ned were found impracticable for use in classifying these large sf 

 endless intermediate conditions being of common occurrence./^'^ffie 

 matter of the determining of names, I am much indebted to pr^XJhler __ 

 and to Mr. Heidemann, the determinations by the former oi mosO^' 

 his own species being of especial value. These determinations,\togat^er 



