UNIVERSITY OF CALIFORNIA PUBLICATIONS 



TECHNICAL BULLETINS 



COLLEGE OF AGRICULTURE, AGRICULTURAL EXPERIMENT STATION 



ENTOMOLOGY 



Vol. I, No. 3, pp. 199-216 February 2, 1916 



SYNOPTICAL KEYS TO THE GENERA OF 

 THE NORTH AMERICAN MIRIDAE 



BY 



EDWARD P. VAN DUZEE 



The following keys cover all but eight of the genera of the 

 ]\Iiridae thus far recorded from America north of Mexico. These 

 eight genera were omitted on account of the want of material 

 for study or because their occurrence in this country is a matter 

 of much uncertainty. Dr. Renter's great work on the Capsidae 

 of Europe {Hemiptera Gymnocerata Enropac, 5 vols., 1878-1896) 

 and his later studies in the North American fauna have formed 

 the foundation for the present paper, although the keys given 

 here are for the most part original. I have found it impossible 

 to work out his subfamilies of 1910 in a satisfactory anal^^tical 

 form, and, while accepting them in my catalogue of our Hemip- 

 tera. I have ignored them in the preparation of these keys, 

 using only his tribes, or divisions as he terms them. In addition 

 to these tribes I have found it both practicable and useful to 

 establish groups of a low^er category in two of the larger tribes 

 which have been denominated divisions with the termination -aria. 

 All sj'nonymy has been omitted here, but it will be given in the 

 catalogue. 



One fact comes out plainly in these studies : that certain 

 characters that are useful for diagnosis in one group may fail in 

 another. This arises from the well-known fact that a character 

 once discarded in the evolution of a group is never revived. Thus 

 we find that the hamus, or vestigial vein, found in the wing-cell 



