Chap. VI. CROSSED AND SELF-FERTILISED FLANTS. 205 



Table LXXXIV. 



Nicotiana tabacum {First Generation). 



their growth taller than the crossed in all the pots except 

 in the crowded one. Accordingly another trial was made, and 

 some of the same crossed and self-fertilised seeds of tobacco 

 were sown thickly on opposite sides of two additional pots ; tho 

 plants being left to grow np much crowded. When they were 

 between 13 and 14 inches in height there was no difference 

 between the two sides, nor was there any marked difference 

 when the plants had grown as tall as they could ; for in one pot 

 the tallest crossed plant was 26s inches in height, and exceeded 

 by 2 inches the tallest self-fertilised plant, whilst in the other 

 pot, the tallest crossed plant was shorter by 3| inches than the 

 tallest self-fertilised plant, which was 22 inches in height. 



As the plants did not grow to their proper height in the above 

 small pots in Table LXXXIV., four crossed and four self-fertilised 

 plants were raised from the same seed, and were planted in pairs 

 on the opposite sides of four very large pots containing rich soil ; 

 bo that they were not exposed to at all severe mutual competition. 

 When these plants were in flower I neglected to measure them, 

 but record in my notes that all four self'fertilised plants ex- 

 ceeded in height the four crossed plants by 2 or 3 inches. We 

 have seen that the flowers on the original or parent-plants which 

 were crossed with pollen from a distinct plant yielded much fewer 

 seeds than those fertilised with their own pollen ; and the trial 

 just given, as well as that in Table LXXXIV., show us clearly 



