MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 23 1 



normal performance of the plant. The above experience leads to 

 the suggestion that the immense economic usefulness of Zea would 

 justifiy a systematic attempt to develop races in which the endosperm 

 would be more perfectly protected from the agencies which usually 

 destroy it. The advantage gained from the use of the additional 

 amount of food would accrue in a shortened vegetative period and 

 stronger and healthier plants, resulting in a more abundant crop at 

 the end of the season. It is more than probable, however, that the 

 very processes of breeding of this species which have been carried 

 on for the purpose of increasing the size of the grain, and the acqui- 

 sition of the qualities that render it more suitable as an article of 

 food have tended to weaken the protective devices of the grain, and 

 to render it more liable to the attacks of destructive agencies. 



The most remarkable species in the matter of the relation of the 

 endosperm to the plantlet are to be found in the Araceae in w^hich the 

 seedling of Arisaema Dracontium and Arum maculatum may carry 

 on their development during the first year after germination entirely 

 at the expense of the material stored up in the seed even when under 

 normal and suitable conditions. The other species, Arisaema tri- 

 fhylliim, with which the tests were made, showed the remarkable 

 capacity of carrying on an amount of growth in darkness fully equal to 

 the normal at the expense of the material stored in the seed. Beyond 

 this it was capable of vegetative activity during the three succeeding 

 seasons in the same manner, a manifestation not exhibited by any 

 other plant, of which records are available. As a result of this action 

 it is to be seen that the starch and other material in the endosperm is 

 hydrolyzed by diastases secreted /;/ sitti, and in the embryo, and after 

 being translocated to the body of the young plant is partially converted 

 to the use of protoplasts, and into their enclosing membranes and 

 included substances. With the death of the seedling nearly all of 

 the plastic material, and the starch which has been laid down in the 

 tissues of the plantlet are again translocated to the tuber formed at the 

 base of the stem. Upon the beginning of a second season of growth 

 the entire process is repeated except that in this, and in the succeeding 

 seasons, the translocations simply move the material up and down the 

 roots and stems of the young plants. The residuum of plastic ma- 

 terial thus undergoes four major translocations and reconversions 

 during the course of life of the seedling which lives three years in 

 darkness. 



