COLOR PATTERN OF ELYTRA. JJ 



of the longitudinal stripes are the normal individual variations, while the 

 lateral unions between stripes are rare and sporadic in their occurrence. 



The stripes are most variable at their ends, especially at the distal end, 

 where the major portion of the variation occurs. The most common varia- 

 tion is the reduction in the length of the stripes, so that they do not reach 

 the posterior angle of the wing (plate 14, figs. 31 to 37). In the different 

 species of the group the variation produced by a reduction in the length of 

 the stripes is always more marked in juncta and defccta than in the others. 

 It is to be noted that reduction in the stripes begins first near the anal edge 

 of the wing and proceeds most rapidly there, and that when stripes are 

 wanting it is the anal and cubital stripes, or those that are morphologically 

 the posterior members of the series, that drop out first, while the subcostal 

 stripes are the least variable and the ones which are last to go in a reduction of 

 pigmentation. At the proximal end the variation is slight and unimportant. 

 The two subcostal stripes differ from the others in their behavior in that in 

 most of the species they are fused at both ends of the elytron, and in juncta, 

 and often in melajiolhorax and rubicunda, along their entire length f plate 14, 

 fig. 38). Variations in these stripes consist in separation, first in the middle, 

 then at the posterior end, then at the anterior end, then the reduction of the 

 posterior member of the pair, and finally of the anterior member ; or this 

 variation may be reversed. 



The transverse fusion of stripes is most common in decemlineata, melano- 

 thorax, and undecimlineata (plate 14). In almost all species this consists in 

 the union of the cubital and anal areas and their further fusion with the 

 medius from the region of the first transverse band through the rest of their 

 length. A common variation is the union of the remaining stripes, the sub- 

 costal and ramous, posteriorly in the region of the fourth transverse band. 

 These variations, which result from the reduction of the anal and marginal 

 portion of the wing, are common in all of the species where fusion occurs. 

 Other transverse fusions of sporadic occurrence are figured on plate 14, 

 figs- 34, 36, and 37. In these we have the union of the ramous and posterior 

 subcostal stripes by means of a transverse band in the region of the first 

 transverse bar (plate 14, fig. 36), of the subcostals in the region of the 

 second transverse bar, and of the ramous and posterior subcostal in the region 

 of the third transverse bar. In the figures on plate 14 it is evident that the 

 transverse fusions, both common and sporadic, occur only at the region of the 

 formation of transverse bars of dark color. This is common in other species 

 of the genus, the one exception being the two subcostal stripes, which, 

 unlike all the other stripes on the elytron, fuse for their entire length. 



In forms like signatico/lis and angustoviltata, where the dark markings are 

 absent, we occasionally find that the position of the stripes is indicated by 

 small deposits of pigment at the proximal and distal ends, especially in the 

 region of the anterior subcostal stripe. 



