1867 ] Relations of Verbasca. 161 



3. V. lyclmitis, alia, by pollen V. tliapsus, alba, is as 39 : 30 of 

 V. lyehnitis, lutea, by pollen of V. tliapsus, alba. 



4. V. lyclmitis, alba, by pollen of V. phceniceum, alba as 56 : 42 

 of V. lychnitis, lutea, by pollen of V. phceniceum, alba. 



5. V. blattaria, alba, by its own pollen, is as 98 : 90 of V. blattaria, 

 lutea by its own pollen. 



6. V. blattaria, lutea, by pollen of V. blattaria, alba is as 96 : 79 

 of V. blattaria, alba, by pollen of V. blattaria, lutea. 



7. V. blattaria, lutea, by pollen of V. tliapsus, alba, as 61 : 43 of 

 V. blattaria, alba, by pollen of V. tliapsus, alba. 



8. V. blattaria, lutea by pollen of V. hjchnitis, alba, as 45 : 36 of 

 V. blattaria, alba, by pollen of V. hjchnitis, alba. 



We thus see, from the eight pure, cross, and hybrid unions of V. blat- 

 taria alba and lutea given in the above comparative table, that though 

 the white variety exceeds in fertility the yellow variety, when both 

 are fertilised by their own pollen, the yellow variety, in the mixed unions, 

 is in every case more highly fertile than the white. In the different 

 unions of V. lychnitis, alba and lutea, there is some little discordance, 

 this, however, is confined to the hybrid unions which are as yet very 

 insufficiently illustrated, as may be seen by consulting Tables 3 and 4. 

 In the case of the pure and cross unions, we see, as in those of V. 

 blattaria, that in the pure unions the white variety, and in the cross 

 unions the yellow variety is the more fertile. 



I know not whether this concordance is casual or otherwise, but I 

 was so forcibly struck with it in the comparative study of my Tables, 

 that I have thus ventured a special statement. I have been more 

 especially induced to notice it also from its evidently bearing and 

 illustrating, as I am inclined to think, that view of Mr. Darwin, (Joe. 

 cit.) respecting the good derived from cross fertilisation ; inasmuch as 

 we see that the yellow and original, or normally coloured, form of the 

 species is less fertile than the white or derivative form in the pure 

 unions, whereas in general, in the mixed unions, the yellow variety 

 relatively exceeds the white in the degree of fertility. Any how, the 

 mere fact of such variations occurring, whether or not they have any 

 bearing on other points of theoretical natural science, seems to me 

 worth noticing, as affording an additional link to that broken chain of 



21 



