444 BUSH-FRUITS 



dom has become more and more apparent. It is easy to 

 describe species so long as single specimens from widely 

 different localities are available, but not easy when the 

 material is more abundant, is drawn from intermediate 

 localities, and represents more varying forms. Then the 

 transitions from east to west, from north to south, from 

 valley to mountain -top and from species to species be- 

 come more apparent. At best it is but passing in 

 review a brief section of Nature's progressive line of 

 march, and it matters little where our lines of division 

 are drawn. If the botanist refuses to enter the garden 

 to see the work of evolution in progress, he may discover 

 the same process by a careful study of a single group of 

 plants like the one in question. 



A single phytogeographical hint brought out by this 

 study may be of interest. In the genus Ribes the flow- 

 ers are for the most part white and rather inconspicuous 

 throughout the eastern portion of the country and on 

 the Plains, with perhaps a slight tinge of color along the 

 eastern coast. In the Rocky Mountains white but 

 somewhat larger flowers are common, while toward the 

 northwest coast large purple flowers become the rule. 

 This color tendency may be only accidental with this 

 genus, for I find no mention of such a tendency among 

 other plants, but Professor Lawrence Bruner tells me 

 that he has noticed a similar color variation in the 

 wings of grasshoppers. 



RIBES, LINN. CURRANT GOOSEBERRY 



Shrubs with simple, alternate, palmately veined leaves, some- 

 times with narrow stipules united with the base of the petiole. 



