'i /:5 



3 1916 



Article V. — Phyllophaga Harris {Lachnosterna Hope) : A Re- 

 zision of the Synonyiny, and one New Name. By Robert D. Glas- 

 gow. Ph.D. 



In few genera of equal economic importance has greater confusion 

 existed, either in collections or in the published work on the group, 

 than in the assemblage of species known to American and English 

 entomologists as Lachnosterna Hope, and to European entomologists 

 as Ancylonycha Dejean. 



JSome years ago the writer turned to this group hoping to make it 

 the basis for a study of some of the problems relating to the origin 

 or source, the diversification, and the dispersal of animal forms in 

 North America. The group offers material that is unsurpassed for 

 such a study. It has a wide distribution, and comprises a great num- 

 ber of species which are relatively sedentary, of large size, and usually 

 aljundant wherever they occur. Moreover, it includes a large and 

 compact series of species which are peculiar tf) the region selected 

 for study. 



It appeared very early, however, that sufficient data were not yet 

 available to warrant such a treatment of the group. Exhaustive col- 

 lections had been made in too few localities, particularly in too few 

 localities that have a critical significance for the group, and the deter- 

 minations in the published lists, based usually upon external characters 

 alone, were too frequently inaccurate to make even the existing rec- 

 ords available for the proposed studies. 



The work of Dr. George H. Horn (1887) on Phyllophaga is more 

 complete and more nearly monographic in nature than that of any 

 other author; yet Dr. Horn says of the group: " It is n(^t surprising 

 that attention has not been given to the species as the literature at 

 present available does not give great assistance, and /'// ;;/_v ozcii case 

 there was almost equal difficulty in arriving at a correct determination 

 of the species 7i'ith the types for comparison along with the literature." 

 And again. Dr. Horn says: "Lachnosterna is certainly one of the 

 most difficult genera in our fauna ".* 



"Itnlics liy piosoiit author. 



