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PROCEEDINGS OF THE NATIONAL MUSEUM 



Remarks. — The color pattern of the elytra in this species, as in 

 other members of the genus, is quite diagnostic, although not, as Horn 

 (1870) states, "remarkably uniform in its system of elytral colora- 

 tion." Plate 1 (fig. 1) illustrates what may be considered the typical 

 pattern. The large black blotches on the posterior half of the elytra 

 may be distinct, as shown, or may fuse with the sutural stripe forming 

 a continuous band across the elytra. This character forms a fairly 

 smooth north-south cline (fig. 1). The percentage of available 

 specimens with the apical blotches fused is very low in the north- 

 em states and Canada and very high in the southern states. In 

 the West Indies and Central America virtually the entire population 

 has the blotches fused. 



100% 



Figure 1. — Diaperis maculata Olivier: percentages represent the proportion of specimens 

 from each state having the apical blotches of the elytra fused, based on at least 25 speci- 

 mens from each state. 



The elongate humeral spot, not shown in the figure because of 

 the convexity of the elytra, is usually present and distinct in northern 

 areas but obsolescent or completely absent in individuals from the 

 Deep South, the West Indies, and Central America. Its presence 

 or absence is quite independent of the fusion or separation of the 

 apical blotches, and was omitted from consideration in studymg 

 the cline described above. It was to the phase in which the 

 apical blotches are fused and the humeral spots absent that Blatchley 

 assigned the name "floridana." 



The two Fabrician species, D. hydactina and D. hydni, both refer 

 to the same insect. In his 1801 paper, Fabricius uses the latter 



