118 A Defence of Menders 



external conditions and on other factors we cannot now 

 discuss. There is as yet no universal law here perceived 

 or declared. 



Professor Weldon passes over the proof of the purity 

 of the germ-cells lightly enough, but this proposition of 

 dominance, suspecting its weakness, he puts prominently 

 forward. Briefest equipment will suffice. Facing, as he 

 supposes, some new pretender some local Theudas- 

 offering the last crazy prophecy, any argument will do 

 for such an one. An eager gathering in an unfamiliar 

 literature, a scrutiny of samples, and he will prove to 

 us with small difficulty that dominance of yellow over 

 green, and round over wrinkled, is irregular even in peas 

 after all ; that in the sharpness of the discontinuity ex- 

 hibited by the variations of peas there are many grades ; 

 that many of these grades co-exist in the same variety ; 

 that some varieties may perhaps be normally intermediate. 

 All these propositions are supported by the production 

 of a collection of evidence, the quality of which we 

 shall hereafter consider. " Enough has been said," he 

 writes (p. 240), " to show the grave discrepancy between the 

 evidence afforded by Mendel's own experiments and that 

 obtained by other observers, equally competent and trust- 

 worthy." 



We are asked to believe that Professor Weldon has 

 thus discovered "a fundamental mistake" vitiating all that 

 work, the importance of which, he elsewhere tells us, he 

 has "no wish to belittle." 



