CAULIFLOWER SEED. 113 



many have in each case, certain features common 

 among themselves which can only be accounted for 

 by the influence of the particular climate in which 

 they are grown. It is, therefore, useless to attempt 

 to maintain these characters wholly unchanged in 

 other climates. Hardiness, earliness, certainty of 

 heading, protection of the head by leaves, and 

 shortness of stem, can all be increased by selection, 

 but, as they are all likewise influenced by climate, 

 the selection is more effective in some climates than 

 in others. The varieties of the south of Europe 

 are as a whole characterized by a long period of 

 growth, tall stems, great vigor and hardiness, and 

 by having the leaves inclined to grow upright and 

 protect the head. 



The cauliflower crosses readily with the cabbage 

 and other varieties and species of the genus Bras- 

 sica. It does not usually flower at the same time, 

 however, as other members of the genus, so the 

 difficulty is not usually great in keeping it pure. 



In France the cauliflower has been crossed arti- 

 ficially with cabbage, turnip and rutabaga, in the 

 attempt to obtain varieties of greater hardiness. 

 Numerous peculiar forms were the result of these 

 crosses, some of which were good cauliflowers, said 

 to be of increased hardiness, but none of them have 

 found their way into general cultivation. One of 

 these, owing to a cross with the turnip, acquired 



