CHAP. II. CROSSED AND SELF-FERTILISED PLANTS. 



31 



of capsules and average number of seeds), the crowded crossed 

 plants produced seeds compared with the self-fertilised as 100 

 to 45. These latter seeds, however, were decidedly heavier, a 

 hundred weighing 41 64 grains, than those from the capsules 

 on the crossed plants, of which a hundred weighed 36 79 grains ; 

 and this probably was due to the fewer capsules borne by the 

 self-fertilised plants having been better nourished. We thus see 

 that the crossed plants in this the first generation, when grown 

 under favourable conditions, and when grown under unfavour- 

 able conditions from being much crowded, greatly exceeded in 

 height, and in the number of capsules produced, and slightly 

 in the number of seeds per capsule, the self-fertilised plants. 



Crossed and self-fertilised Plants of the Second Generation. 

 Flowers on the crossed plants of the last generation (Table I.) 

 were crossed by pollen from distinct plants of the same genera- 

 tion ; and flowers on the self-fertilised plants were fertilised by 

 pollen from the same flower. The seeds thus produced were 

 treated in every respect as before, and we have in Table II. 

 the result. 



TABLE II. (Second Generation.') 



Here again every single crossed plant is taller than its anta- 

 gonist. The self-fertilised plant in Pot I., which ultimately 

 reached the unusual height of 80| inches, was for a long time 

 taller than the opposed crossed plant, though at last beaten by 

 it. The average height of the six crossed plants is 84* 16 inches, 

 whilst that of the six self-fertilised plants is 66 '33 inches, or 

 as 100 to 79. 



Crossed and self-fertilised Plants of the Third Generation. Seeds 

 from the crossed plants of the last generation (Table II.) again 



