DISSEMINATION AND LEAF REFLEXION OF YUCCA. 93 
nation. They evidently fall as soon as mature while still 
soft and tempting to animals. If this is so they may be 
gathered regularly by certain small mammals that carry them 
about and eat merely the pulp, discarding the core 
and seeds as we discard the apple core. Such animals 
would be prevented by the reflexed leaves from climbing 
the stems of the plants and securing the fruits in this man- 
ner. It is thus necessary that the fruits fall in order that 
they may be secured and carried off. In Yucca aloifolia, 
with which we will have most to do, this core does not 
occur. In the still unripe but nearly mature fruits one 
may get a suggestion of it in the rather firm, white mem- 
brane which immediately surrounds the seeds. As the 
fruit matures, bower it becomes soft throughout and 
this is doubtless of decided importance in its dissemination 
as it thus affords no resistance or hindrance to birds eating 
the pulp from obtaining the seeds at the same time. 
In regard to the dissemination of Sarcoyuccas, Trelease * 
writes ‘* These fruits are well adapted to dissemination by 
fruit-eating animals, especially birds, the seeds being thrown 
away, but I do not know of any recorded observations on 
their dissemination.’’? This was the condition of our under- 
standing of their dissemination, when in the fall of 1892 I 
came to Florida and was afforded opportunity to study Y. 
aloifolia in its native home. One day a mocking bird was 
noticed picking at the pulp of the ripe fruits and this led 
to an investigation of the subject of its dissemination. 
The fruit of Yucca aloifolia (Plate 47, fig. 1) is elon- 
gated elliptical in outline, with usually a slight central 
constriction, though this is by no means always the case. 
They sometimes reach a length of 15 centimeters but are 
usually from 8 to 10 centimeters long. In cross section 
(Plate 47, fig. 2) the fruit is hexagonal in shape, caused 
by the spreading of the nectar grooves in the ripening of 
the fruit. The openings of the septal nectaries may be seen 
* Trelease, Wm., “Further Studies of Yuccas and their Pollination,’’ 
l.c., p. 224, 
