192 IOWA ACADEMY OF SCIENCES. 



while of sub-sp. II, lineatocoUis, var. a and b occur only in Cal- 

 ifornia, Arizona and Colorado, and var. c and d have only been 

 reported from Maryland and West Virginia. Sub-sp. Ill 

 oshorni, var. a, has a wide range, while var. & {testacea) and c 

 {pi7u) are only found on the eastern coast from New York to 

 North Carolina. 



C.proteus, sub-sp. I, Jlava, is found throughout the northern 

 half of the Mississippi valley and the eastern states up to Can- 

 ada, while sub sp. II and III, vlttata and nigra, are found only 

 in Pennsylvania and the surrounding states. Both varieties of 

 xanthocephala have the same wide range: the southern part 

 of the United States, from Maryland to Iowa on the north to 

 Florida and Texas on the south. C. delicata with all of its varie- 

 ties ranges from Colorado to California, and from Utah to 

 Arizona. 



ECONOMIC IMPORTANCE. 



As a whole they are of considerable economic importance. 

 Although not usually occurring in sufficient numbers to be 

 noticeably injurious, however, proteus has been reported as 

 having done considerable damage to cranberry swamps in a 

 number of instances. Their food habits have not been very 

 accurately determined. In general they feed on the sap of 

 trees and shrubs, occurring most abundantly in low places. 

 They have been reported as occurring on the ash, oak, pine, 

 alder, butternut, elder, blueberry, cranberry and some of the 

 larger grasses and weeds. 



SUMMARY. 



The study of this genus just recorded only adds one more 

 instance to the many giving evidence against the immutability 

 of species. Here we have four species, of which the larger and 

 lighter varieties are widely separated, and easily recognizable 

 by constant and strikingly distinct color markings, while at 

 the other end of the series are small dark forms only capable 

 of separation and recognition by reference to structural char- 

 acters rendered indistinct by deep coloration. To still more 

 complicate matters, proteus excepted, they have intermediate 

 light green or glaucus forms which so grade into each other in 

 size and shade that it is only on structural characters in gen- 

 eral, and the shape of the apical cells, in particular, that they 

 can be separated. 



