110 MISSOURI BOTANICAL GARDEN. 
grow on prairies or in open fields, and elata is a plant which 
frequents the open mesas of the Arizona plains. Those 
Yuccas which are dependent on the wind for their dissem- 
ination apparently always grow in open places where the 
wind has free action upon them. The Sarcoyuccas on the 
contrary frequently grow in wooded areas, mountainous 
districts, ete. Aloifolia sometimes grows in dense ham- 
mocks. Macrocarpa, Prof. Toumey reports as a strictly 
mountainous plant, frequenting shady cafions in Arizona.* 
Habitat evidently has important connection with the 
methods of dissemination employed by the various species. 
The peduncles in jilamentosa, some time after the fruits 
have ripened, very commonly rot at the base and fall. This 
serves to empty the few seeds which may remain in the 
capsules at some distance from the parent plant. The 
peduncles in this species vary, in Florida, from 3 to 12 feet 
in length. 
SUMMARY. 
In Yuccas the three types of fruits, characterizing the 
different groups, correspond to three types of dissemina- 
tion. 
The Sarcoyuccas, having fleshy fruits, are probably in- 
tended for dissemination by fruit-eating animals. 
In the fleshy fruits of baccata, valida and Guatemalensis 
the seeds are surrounded by a papery core similar to that 
of the apple. The fruits of these species drop early, prob- 
ably as soon as mature. This seems to be a device to aid 
in their dissemination. They are probably gathered by 
- small mammals that eat the pulp, the seeds, which are 
protected by the core, being discarded. 
The fruit of alocfolia, which is fleshy throughout and 
persistent, is principally disseminated by the mocking 
bird. This is accomplished by the bird swallowing the 
seeds while eating the pulp. The seeds remain uninjured 
* Toumey, J. W., “‘ Notes on the Tree Flora of the Chiricahua Moun- 
tains.’”” Garden and Forest, VIII. (Jan. 16, 1895), p. 22. 
