5i6 



BOTANICAL GAZETTE 



[DECEMBER 



sprout-tubers appeared to be emerging through the skin from within 

 the potato (fig. 2). Closer observation and dissection disclosed 

 the interesting fact that at least a quarter or a third of the potatoes, 

 of which there was about a bushel in all, had ingrowing sprouts. 

 The condition is well illustrated in fig. 3, which is a typical cross- 

 section. 



On careful dissection of many of the tubers, the ingrowing 

 sprouts were found to ramify in every direction throughout the 



Fig. 4. — Tubers of Solatium tuberosum with ingrowing sprouts: the figure at the 

 right shows the ingrown sprouts emerging through the skin; the figure at the left is 

 of a dissection, showing rootlets, the marked development of lenticels, and the tuberiza- 

 tion of some of the branches of the ingrown sprouts within the old tuber (cf. figs. 2 

 and 5). 



tissue of the potato. The atrophied and etiolated bud end retained 

 the characteristic nutation curvature, but the sprout was frequently- 

 more or less enlarged just back of the tip (figs. 4 and 5). Lenticel- 

 like openings were well developed in the epidermis of the sprouts, 

 often giving them the appearance of a cylindrical file. 



Numerous fibrous roots grew out from the branches, and they 

 seemed, for the most part, to be confined in their growth to the 

 channels made by the stem. As is clearly shown in the right hand 



