PLANTS OF SPECIAL INTEREST. OD 
textile species occurs on the island no fruit of course is produced by 
it. The importance of collecting the flowers and preserving them 
carefully in alcohol or formalin is evident, as well as the necessity of 
making photographs of the growing tree to show its habit, the char- 
acter of its bark, its method of branching, its fascicles of leaves, and 
the emergences on its stem and aerial roots. 
BANYANS, MANGROVES, AND EPIPHYTES OF THE FOREST. 
Of special interest on account of their method of germination and 
growth are the giant banyans (/“evs spp.) of the forest, the mangroves 
of the brackish estuaries, and certain epiphytal eryptogams and other 
plants. 
The banyans usually begin their existence upon other trees, sending 
down aerial roots which interlace and grow together, clasping the 
trunk of their host and eventually strangling it. They then lead an 
independent existence, their great spreading limbs sending down more 
roots, which are like pendent threads at first, but soon thicken after 
gaining a foothold in the earth, and serve as columns to support the 
great dome of foliage overhead, as well as to supply it with nourish- 
ment and moisture (Pl. VIII). 
The chief interest in the mangroves (Rhizophora and Bruguiera) lies 
in the fact that their fruit germinates while still attached to the tree, 
the spindle-shaped radicle perforating the apex of the fruit, elongating 
and hanging vertically downward. When the fruit falls the radicle 
sticks into the soft mud below, retaining an upright position, like. a 
stake thrust into the ground, and resisting the current of the tide as 
it ebbs and flows. 
The forest epiphytes are not well known, owing to the difficulty in 
collecting them. Care should be taken to visit clearings where forest 
land is being prepared for planting. In such places good material can 
undoubtedly be collected. The most interesting epiphyte thus far col 
lected in Guam is Dischid/a puberuia, which belongs to a genus havy- 
ing some of their fleshy leaves modified into urn-like receptacles. 
These usually contain water, and the adventitious roots of the stem 
often creep into them, as if for nourishment or moisture. 
PLANTS THAT SLEEP. 
Among the Guam plants there are a number which exhibit in a 
marked degree the phenomenon known as ‘‘ sleep movements,” folding 
their leaves each night and opening them again at sunrise. Some of 
them (Acacia furnesiana and Abrus abrus, Pl. XXXII), are so sensi- 
tive to changes in the intensity of light that they go to sleep if the 
sky suddenly becomes overcast, and wake up when the sun reappears. 
Most of these plants are leguminous, but there is one remarkable 
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