TAXONOMIC VALUE OF MORPHOLOGICAL CHARACTERS 



17 



them to "form a working basis" for their separation. It may be pointed 

 out that the use of more individuals would in all probability have in- 

 creased the difficulty in distinguishing between the graphs due to the 

 introduction of extreme forms. 



Fig. 8.^-Pseudococcus maritimus (Ehrh.) ; antennal graphs drawn from specimens 

 from various hosts and localities. 



Fig. 9Pseudococcus maritimus (Ehrh.) ; antennal graphs of specimens taken 

 from Mesembryanthemum at La Jolla (above) and Rubus vitifolius at Stan- 

 ford University (below). The shaded area indicates the gap between the 

 two. 



In text figure 9 are shown the graphs obtained from specimens of 

 P. maritimus taken from Mesembryanthemum at La Jolla, Calif., and 

 from Rubus vitifolius at Stanford University. There is more difference 



