1922] Graham: Wing Venation of Coleoptera 191 



New Jersey Tea (Ceanothus americanus). 

 Large toothed aspen (Populus grandidentata). 

 Carolina poplar (Populus eugenii). 

 Lombardy poplar (Populus nigra, var. italica). 

 Trembling aspen (Populus tremuloides). 

 Witch-hazel (Hamamelis virginiana). 



The biological development of the individuals occurring 

 on American ash, European ash, fringe tree, laurel leaved 

 willow, large toothed aspen, and Lombardy poplar has been 

 followed and found to agree closely throughout the life cycle 

 with that of the lilac form. 



In conclusion it may be said that the evidence certainly 

 seems to justify an affirmative answer to the question, "Are 

 there two species of the Oyster-shell Scale?" 



LITERATURE CITED. 



Cockerel!, T. D. A. Miscellaneous Notes on Coccidae. Can. Ent., 1895, 27:259. 

 Frank, A. B. and Kruger, F. Schildlausbuch, 1900, 95. 



Glenn, P. A. Forms of the Oyster-shell Scale in Illinois. Jour. Econ. Ent., 

 April, 1920, 13:173-177. 



A STUDY OF THE WING VENATION OF THE 

 COLEOPTERA.* 



By S. A. Graham. 



The purpose of the modern taxonomist is not satisfied by 

 the mere arbitrary naming of an insect. Taxonomy is more 

 than that. If the worker in this field is true to the highest 

 ideals of his profession he must continually strive to clear up 

 some of the multitude of problems associated with the natural 

 relationship of the organisms with which he is dealing, and to 

 show this relationship in his classifications. 



Unfortunately valuable phylogenetic characters are some- 

 times accidentally overlooked and remain in obscurity. It is 

 not until we take advantage of all these available characters 

 that we can hope to arrive at a true expression of phylogenetic 

 relationship. 



In the Coleoptera the characters to be found in the hind 

 wings are undoubtedly of considerable value, but have been 

 almost entirely neglected in taxonomic studies. This is 



*Published with the approval of the Director as Paper No. 228 of the Journal 

 Series of the Minnesota Agricultural Experiment Station. 



