426 BROOKLYN BOTANIC GARDEN MEMOIRS 



small external tubers was removed. The changed pose in Fig. 3 

 brings to view a second new tuber not shown in Fig. 2. 



The larger of the new tubers was borne on a very short branch 

 three centimeters from the point of origin of the sprout; and the 

 smaller one on a similar branch about a centimeter beyond. The 

 course of the ingrowing sprout was perpendicular to the surface of 

 the parent tuber at the point of origin. Apparently, the direction 

 of growth had been inward from the beginning. Close observation of 

 this and some other specimens revealed nothing to indicate that the 

 sprouts had started externally and turned inward. Whether it was 

 the tip of the sprout or the expanding tubers which first broke through 

 the cortex cannot be determined in this case; but in other specimens 

 (among them the one shown in Fig. i) it was clear that the new tuber 

 had been responsible for the rupture of the cortex. 



The ingrowing sprouts exhibited the lenticel-like openings observed 

 by Gager. These signify nothing except that the sprouts were 

 formed in a humid atmosphere. The fibrous roots observed by 

 Gager were lacking and the sprouts were but slightly branched. 



The strange behavior of these tubers cannot be ascribed to low 

 vitality. This is shown by the fact that a large number of tubers 

 from the same lot were planted and a good stand of vigorous plants 

 obtained. 



In the main, these observations agree with those made by Gager 

 and add nothing to them except to show that tubers of considerable 

 size may form on ingrowing sprouts and produce a striking freak of 

 nature. The internal tubers observed by Gager were small ones. 



