162 



On the Reproductive Functional 



[No. 3, 



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

 nomena of mongrelism and hybridism. 





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lation. 







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The 

 comparative 



Table 7. — Pure and Mixed Unions 





m 



of Verbascum thapsus, lutea, 



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fertility of 



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the diffei'ent 

 unions. 





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r ft 



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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. lychnitis, lutea, L., . . 



6 



1 



54 



54 



20 



1080 



... 



465.2 



4. V. thapsus, lutea by pollen 



















of V. lycJmitis, var. alba of 

















. 



gardens, 



6 



3 



187 



G2 



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. virgatwm, 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. lychnitis on the stigmas of the yellow variety of V. thapsus ; 

 the pollen of V. lychnitis, alba, exceeding in its fertilising influence 

 that of V. lychnitis, 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. virgatwm and V. blattaria, 



