THE SWEET POTATO. 75 



while some have part or the entire heart of the tuber 

 stained with pnrple. 



About as definite a character as the color of the 

 flesh is the distinctness of the bundles which are 

 scattered irregularly throughout the mass of the 

 starch-bearing tissue of the tuber. In a few varie- 

 ties a freshly cut tuber shows at a glance the loca- 

 tion of these bundles. Small, sharply-marked spots 

 dot the surface, standing out "distinctly." In most 

 tubers a freshly cut surface shows to a certain extent 

 the location of the bundles, but the bundles appear 

 only as slightly darker areas or watery specks not 

 sharply cut off by a line from the surrounding tissue. 

 The bundles appear "blurred." Still other tubers 

 show no indication of the position of the bundles on 

 a freshly cut surface. In these the bundles are "not 

 visible." 



It is certainly desirable that other important 

 characters, such as dryness or dampness of the 

 flesh of the cooked tubers, flavor, earliness, etc., 

 should be considered in a comparative classification. 

 So far the writer has not succeeded, however, in 

 establishing standards of flavor, and he was not in a 

 position to make tests of the dr^mess and earliness 

 of the tubers. The description of the varieties, as 

 given later on, will therefore only serve to distin- 

 guish them, and not as an index to their market value. 



C. Key to Vameties. 

 With all the above facts in his possession, the 

 writer began to evolve a key. The style of key that 

 naturally suggested itself was the one commonly 

 used in botanical text-books for the determination 

 of species. After careful thought the writer 

 decided to use the key given below, although it 



