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ON THE NORTH AMERICAN SPECIES OF THE SUBGENERA DIASPIDIOTUS AND 

 HEMIBERLESIA, OF THE GENUS ASPIDIOTUS. 



WILMON NEWELL. 



The two subgenera, Diaspidiotiis and Hemibcrlesia, in- 

 clude the majority of the Nt)rth American species of Aspidiotus. 

 They include, too, some of the most destructive species. 

 Perhaps no insect of America is better known to-day than 

 one member of this grcup, A. pcrniciosjis. 



The writer is studying;- this group. This paper is not 

 presented with the assumption that it is in any sense a com- 

 plete treatment of the subject. It is presented rather as a 

 preliminary, a short summary of the present known North 

 American species with characters of identification which it is 

 hoped will be of some little assistance to students and others 

 interested in these forms. 



The object has been to arrange the species in the key 

 with reference to their natural relationships. Subsequent 

 study will doubtless show that some of the inferences drawn, 

 are incorrect. Should this paper be the cause of the dis- 

 covery of new or different relationships of any one species to 

 any other it will have accomplished its mission. 



The two subgenera considered represent a division of 

 Aspidiotus specialized in a definite direction. Of Diaspid- 

 iotus, as Prof. Cockerell says, A. ancylus may be taken as 

 the type. This subgenus is temperate in distribution and is 

 nsually characterized by small, dull colored, inconspicuous 



