DISPERSAL OF PLANTS BY OCEAN CURRENTS. 75 
Frurrs witht Buoyant Husks. In addition to the coconut, which 
is provided with a fibrous envelope, and is known. to float for long 
periods of time in the sea without losing its vitality, there are found 
in the drift of Guam the fruits of Barr/ngtonia speciosa, called ** put- 
ine” by the natives, and Ochrosia mariannensis, called ** fago.” Both 
of these fruits have fibrous husks, but that of the Barringtonia has a 
hard glossy surface, somewhat as in the case of the coconut, while the 
surface of the Ochrosia is soft and easily eroded. The fruits of this 
Barringtonia (Pl. XXXVIIJ) are four-cornered and miter-shaped; 
‘he natives crush them and use them as a fish intoxicant. Those of the 
Ochrosia are oval in shape, and, like the closely allied Cerbera fruits 
of Samoa and other tropical countries, are soon deprived of their pulpy 
parenchyma, and display the cushion of fiber inclosing the mesocarp. 
This owes its buoyancy to intercellular air spaces. It is elastic and 
serves to protect the seed from erosion and from the attacks of animals. 
MANGROVE FRUITS. —Great numbers of these spindle-shaped young 
plants are continually carried by the tide from the estuaries into 
which they drop after having begun to germinate on the tree. The 
fruits of RA‘zophora mucronata (Pl LXV) are easily distinguished 
from those of Bruguiera qymnorhiza (Pl. XL) by the four-parted 
persistent calyx, the calyx of Bruguiera consisting of many segments. 
Associated with them are found the seeds of the ‘*red-flowered 
mangrove” (Lumnitzera Uttorea), called ‘ata’ in Guam; those of 
Ereoecaria agallocha, the “milky mangrove,” or **blinding-tree,” 
which grow in catkin-like spikes; and the keeled nuts of the ‘Sufa” 
Cberiticrn Uttoralis), the hard shell of which includes a very large 
air space (PI. LIT). 
LIrroRAL TREES AND sHRuBS.—Other seeds found in the drift are 
those of Pariti tiliaceum and Thespesia populiea, the **pago™ and 
‘‘kflulu” of the natives, both of which belong to the Malvaceae, and 
have cavities filled with air; the round nuts of Calophylum ‘nophyl- 
Zum, called ‘*daog;” the boat-shaped “almonds” of Zerui/nalia catappa, 
called “talisai,” often much eroded; the angular woody seeds of the 
‘“lalanyug” (Yy/ocarpus granatum), and the ribbed fruit of the nipa 
palm (Mypa fruticans). Among the plants which grow on the edge of 
the sea, whose fruit drops into the water continually, are the shrubby 
Lobelia koenigii and Tournefortia argentea (Pl. LUXVIID, associated 
with the creeping ** goats-foot convolyulus” (/ponmoeca pes-caprae), the 
seeds of which contain air cavities, and the ‘Polynesian ironwood ” 
(Casuarina equisetifolia), the cones of which (Pl. XLD) are corky and 
buoyant and inclose seeds provided with wings which adapt them for 
transportation by the wind. The transparent wings of these seeds are 
stiffened by the persistent style. When a handful of them is thrown 
into the air they resemble a swarm of flying insects. Hundreds of 
these seeds, together with the queer-shaped Barringtovia fruits, are 
