60 IPOMCEA PURPUREA. CHAP. IL 



as those of a wild species growing in a state of nature ; 

 whether the same tint occurred, as is probable, in the 

 earlier generations, neither my gardener nor self could 

 recollect. The flowers on the plants which were first 

 raised from purchased seed, as well as during the first 

 few generations, varied much in the depth of the 

 purple tint ; many were more or less pink, and occa- 

 sionally a white variety appeared. The crossed plants 

 continued to the tenth generation to vary in the same 

 manner as before, but to a much less degree, owing, 

 probably, to their having become more or less closely 

 inter-related. We must therefore attribute the extra- 

 ordinary uniformity of colour in the flowers on the 

 plants of the seventh and succeeding self-fertilised 

 generations, to inheritance not having been interfered 

 with by crosses during several preceding generations, 

 in combination with the conditions of life having been 

 very uniform. 



A plant appeared in the sixth self-fertilised genera- 

 tion, named the Hero, which exceeded by a little in 

 height its crossed antagonist, and which transmitted 

 its powers of growth and increased self-fertility to its 

 children and grandchildren. A cross between the 

 childien of Hero did not give to the grandchildren 

 any advantage over the self-fertilised grandchildren 

 raised from the self-fertilised children. And as far as 

 my observations can be trusted, which were made on 

 very unhealthy plants, the great-grandchildren raised 

 from intercrossing the grandchildren had no advantage 

 over the seedlings from the grandchildren the product 

 of continued self-fertilisation ; and what is far more 

 remarkable, the great-grandchildren raised by crossing 

 the grandchildren with a fresh stock, had no advantage 

 over either the intercrossed or self-fertilised great- 

 grandchildren. It thus appears that Hero and ita 





