16 



THE VARIATION AND CORRELATIONS OF 



more variable in length than the ovipositor, and the posterior femora 

 are less variable than either; while the order of variability for the long- 

 winged portion of the genus and also for the long- winged portion of the 

 Gotha collection the only local collection I have which gives such data- 

 is ovipositor, posterior femora, tegmina. 



TABLE 9. Comparison of intraspecific and interspecific correlations, 

 [a, short-winged; b, long-winged.] 



Table 9 offers a comparison of the intraspecific and the interspecific 

 correlations. The intraspecific coefficients of correlation are averages 

 obtained from the same collections as were the average coefficients of 

 variation given in table 8. Those intraspecific coefficients which are 

 larger than the corresponding interspecific ones are italicized. Here, 

 again, not much stress can be laid upon the constants involving body- 

 length. The table seems to indicate that, on the whole, the intra- 

 specific correlations between these various organs are approximately 

 equal to the interspecific. There is, at any rate, no constant difference, 

 and such differences as there are are not great, considering the prob- 

 able errors. 



TABLE 10. IntersjiccijU- third 



Short-winged. 



Body +1.1381.324 



Tegmina -| 0.362^ 0.790 



Posterior femora 0.078^0.345 



Ovipositor 0. 917:+ 1.680 



1. 360 d 0.659 



-1.481 0.248 



+0.0450.227 



+0. 664 .i- 1.055 



This similarity of conditions in the genus as a whole and in separate 

 portions of it is further illustrated by the relation between the long- 

 winged and the short-winged dimorphs. Table 80 shows that the means 

 of all the organs studied of the short-winged group of the genus are 



