162 



On the Reproductive Functional 



[No. 



evidence which is said to disjoin the serial continuity of the phe- 

 nomena of mongrelism and hybridism. 







erti- 

 pro- 





CO 



CD 



CD 



By calcu- 

 lation. 







E 7. — Pure and Mixed Unions 



to 1 o 



a 2 





CO 



6 





The 

 comparative 



Tabi 





CO 



of 

 L. 



Verbascum tha/psus, lutea, 

 as $. 



o 

 & . 



o <g 



-si 



Pa 

 7t • 



O g 



^3 



<s 

 as 



CO 



o 



"qfi o 





CD 



CD 

 m 







fertility of 



the different 



unions. 







6 - 13 



6 ^ 



6 



CD o 



> ^ 



o ^ 



S3 a 



6 









Z 



£ 



£ 



<l 



6 



& 





No. 









1. 



Verbascum thapsus, lutea, L. 





















by own pollen, 



8 



8 



920 



115 



20 



2300 



1000 





2. 



V. thapsus, lutea by pollen 

 of V. thapsus var. alba of 





















gardens, 



4 



2 



218 



109 



20 



2180 





947.8 



3. 



V. thapsus, lutea by pollen 





















of V. lyclinitis, lutea, L., . 



6 



1 



54 



54 



20 



1080 





465.2 



4. 



V. thapsus, lutea by pollen 

 of V. lyclinitis, var. alba of 





















gardens, 



6 



3 



187 



62 



20 



1246 





541.7 



5. 



V. thapsus, lutea by pollen 

















. 





of V. nigrum, L., 



10 



4 



275 



69 



20 



1375 





597.8 



6. 



V. thapsus, lutea by pollen 





















of V. pyramidatum, Beib., 



10 



6 



374 



62 



20 



1246 





541.7 



7. 



V. thapsus, lutea by pollen 





















of V. thapsiforme, Schrad, 



10 



8 



408 



51 



20 



1020 





443.2 



8. 



V. thapsus, lutea by pollen 





















of V. virgatum, With., 



' 10 



5 



222 



44 



20 



888 





386.0 



9. 



V. thapsus, lutea by pollen 





















of V. blattaria, lutea L., . . 



1 8 



3 



98 



33 



20 



653 





283.9 



In Table 7 we have several unions of the yellow variety of V. 

 thapsus. If we compare these results, we see that the fertility of the 

 V. thapsus, lutea, by its cross-unions with the V. thapsus, alba, is 

 decreased in the proportions of 94 relatively to 100, the product of 

 fertilisation by its own pollen. We also see a great difference in the 

 degrees of potency of the two pollens of the white and yellow variety 

 of V. lyclinitis on the stigmas of the yellow variety of V. thapsus ; 

 the pollen of V. lyclinitis, alha, exceeding in its fertilising influence 

 that of V. lyclinitis, lutea, in the proportion of 54 : 46. Judging 

 from the results of the seven hybrid unions given in this Table, we 

 also see how little the recognised systematic affinities of species guide 

 us in pronouncing a priori as to the degree of fertility of their several 

 unions. For example V. thapsiforme, V. virgatum and V. blattaria, 



