1908.] 



IMPROVEMENT OF THE POTATO. 



385 



3. THE MODERN PLANT 

 STRUCTURE AND CHARACTERISTICS 



The potato is an annual, and in its original state reproduced 

 freely by seeds. The tubers were then so small that it is doubtful 

 whether the plant would have been preserved to us by this alternate 

 means of reproduction. At present, however, many varieties never 

 or at most rarely seed, and the plant has become virtually a peren- 

 nial through its tubers. 



Baker (6) gives the following technical description of a wild 

 plant : 



"Leaves pseudo-stipulate, a fully developed one about half a foot long, 

 with seven to nine finely pilose, oblong-acute, large leaflets, the side ones stalked 

 and unequally cordate at the base, the one to two lowest pairs much dwarfed, 

 leaving a naked petiole about an inch long; the rhacis furnished with numerous 

 small leaflets interspaced between those of full size. The flowers arranged in 

 compound terminal cymes, with long peduncles; pedicels hairy, articulated 

 about the middle. Calyx hairy, one-fourth to one-third inch long, teeth deltoid- 

 cuspidate, as long as, or a little longer than, the campanulate tube. Corolla dark 

 lilac, subrotate, nearly an inch in diameter, pilose externally; segments deltoid, 

 half as long as the tube. Anthers bright orange-yellow, linear-oblong, nearly 

 one-fourth inch long, filaments very short. Berry perfectly globose, smooth, un- 

 der an inch in diameter." 



This description perfectly fits the cultivated potato of today, as 

 Baker has already noted, with the exception that the lobes of the 

 calyx are now a little more pointed. 



I 



FIG. 3. PARTS OF POTATO FLOWER. 



a. Back side of anther. c. Front side of anther. 



b. Pistil. d. Cross section of anther. 



e. Tops of anther showing the openings. 



