16 ILLINOIS BIOLOGICAL MONOGRAPHS [410 



with the spots in the upper right-hand third of the elytron missing. 

 Figure 6 shows a suggestion of seven cross bands as numbered. Figures 

 8 and 9 are similar but somewhat broken and with some tendency to 

 forming longitudinal stripes between the tracheae. Figure 9. Plate I 

 shows a longitudinal row of spots and figures 10 to 13, Plate II either 

 rows of spots or continuous longitudinal bands between the tracheae. 

 Figures 14 to 21, Plate III show forms that have lost most of their pig- 

 ment and have retained it only in the lines of the tracheae. Figure 18 

 shows a form that appears to have double longitudinal lines between the 

 tracheae and has lost the unpigmented areas in the anterior part of the 

 elytron. Figures 16, 20, and 21 show forms that are highly specialized 

 as to the patterns and have lost most of the pigment and the media 

 trachea is almost gone. It will be noted that there are many interesting 

 curves and branches that are related to the color pattern. 



Figures 23 to 25, plate III show an oblique joining of the markings 

 to form a vitta that is not related to the trachea and is rather rare, con- 

 stituting an exception to the usual rule. 



As a result of this study of the figures it is seen that in the color 

 patterns of the genus Cicindela exists a system of markings that is related 

 to the tracheae, and also is arranged with reference to the cross bands 

 of which there are five, two of which may be divided as to make seven 

 and that these are arranged as follows : There is a cross band in the 

 center of the longest measurement of the elytron. This location is 

 shown to be the same in essentially all of the cases by actual measure- 

 ment. There is one at the tip and one at the base, with one or two 

 arranged respectively between each of the latter and the middle one. 

 These intermediate bands are most commonly represented as one but 

 are some times divided, but in any case its center, or the center of the 

 intervening pigmented area is half-way between the two adjacent, un- 

 pigmented more permanent cross bands. It is also evident that there 

 is a possibility of fusion of joining of light areas, so that these lines of 

 fusion are in the spaces between the tracheae and in the region of the 

 cross bands. 



The areas near the hairs described in a preceding section are the 

 very last to lose their pigment in the forms that become almost entirely 

 without pigment. It is to be noted that in the forms that have the 

 longitudinal stripes and cross bands broken up, the media is almost 

 entirely gone. It has been shown that these cross bands are the most 

 constant wing markings in insects and are usually represented as the 

 five first mentioned. I have gone over very large series of Coleoptera, 

 (Tower, 1906), and find that this is true for this order, while cross 

 bands in the Lepidoptera (Braun, et al. cited), Diptera, Orthoptera, 

 Tricoptera, Plecoptera, Hemiptera, have been discussed by Von Linden, 



