54 ILLINOIS BIOLOGICAL MONOGRAPHS [448 



ern Great Plains. In the New Mexico localities dark brown forms 

 (cimarrona) occur. There is no correlation between color and mapped 

 climatic conditions unless it be rainfall. 



Considering the purpureas in which the reduction of markings 

 leaves only a small dash at the margin of the elytron, one notes that 

 the wine colored specimens are distributed throughout the region of 

 the Great Lakes and in Manitoba and generally westward to the Mis- 

 souri River, and Colorado. This type is distributed in a general way 

 north of about 41 degrees North Latitude and has the thorax the same 

 color as the elytron. The forms splendida and transversa are similar 

 in color but have the thorax green or blue and the elytron either red 

 or wine color, they are distributed south of the form with red thorax 

 and in the eastern part of the range are less brilliant than farther 

 west. The more western forms have brilliant red elytra similar in 

 color to that of the red scutellaris. Mixed with these are the green 

 forms ; in western Kansas and Colorado, especially, they occur with the 

 red forms and are often taken in coitus with them. The green form 

 is evidently merely a color aberration of the red form. 



The color variation of C. tranquebarica is not striking over the 

 entire area east of the Rockies. Nearly all are simply dull brown. 

 Specimens from the moist southern states are usually duller blackish 

 brown than the northern forms. No striking color varieties occur even 

 east of the Pacific states and Idaho. In some parts of eastern Califor- 

 nia (Bridgeport) they are brown, while only a little way west they 

 are green ; further surprising differences were found in Nevada. At 

 Caliente the writer took brown tranquebarica and blue oregona, while 

 at Las Vegas he took green and bluish tranquebarica and no oregona 

 v, hich occur there and are probably green also, but there is no apparent 

 reason why oregona should be blue or green and tranquebarica brown 

 in a region where both are likely to be green. 



C. generosa is brown and wine color in eastern localities and 

 where purpurea is similarly colored. Near Chicago the colors are simi- 

 lar. At Topeka, Kansas, the color varies considerably, reddish, bluish, 

 and greenish brown occur. South, and southwest from this point the 

 specimens are progressively redder. The most brilliant forms are the 

 red ones from western Oklahoma, western Texas, and Colorado. At 

 low altitudes these are golden red. Wine red occurs at high altitude 

 (Salida, Colorado, 7,000 ft.). C. hirticollis has already been discussed 

 (see page 49). With the exception noted there is little variation and 

 distribution is transcontinental and from the Great Lakes to Vera Cruz. 



