The Vegetation 
The greater portioh of the lahd area of Fanning Island is covered 
with Cocos plantations. This type of vegetation dominates all of the 
dry land portions of the south island, the northeast island and about 
eighty percent of the northwest island. On the latter one finds a 
Pisonia forest and open clearings with Tournefortia and Pandanus . A 
rim of Tournefortia and occasional Sceavola is found around the lagoon 
rim. Scaevola is the usual shrub on the seaward side of the islets with 
Tournefortia occuring in depressions in back of the beach. Fanning Island 
is unique in that large areas are covered with silty flats and mounds 
periodically covered with water at exceptionally high tides. Many of 
these flats near the periphery of the lagoon or in bays of the lagoon 
remain dry for long periods and are covered with an association of 
Heliotropium and Lepturus . Many of these areas are mounded with water 
channels between. These mounds are often vegetated with Lepturus and 
Heliotropium especially near the dry shore. Interestingly, the antici- 
pated Sesuvinm rarely formed extensive mats in these areas but was common 
near the shore of the lagoon in those areas where the lagoon waters 
increased in depth rapidly from the shore. In these situations Sesuvium 
was found in sandy soil Over a coralline hardpan. The roots of the plants 
are found penetrating into the hardpan. At the edge of the Cocos planta¬ 
tions and under the Cocos, Pisonia and Tournefortia forests the ubiquitous 
Polypodium scolopendria is common. This species is found on most of the 
wet islands of the Pacific and usually, but not in this case, with Asplen l 
nidus. This fern is also found on Palmyra and Washington Islands in the 
Line Group 
Several weedy grasses were found on the island particularly around 
the settlement and spreading to the roads and disturbed areas of the Cocos 
plantations. The most commonly encountered species in this group is 
Eragrostis tenella . Also common on the south and northwest island are 
Cenchrus echinatus and Stenotaphrum secundatum . The latter is especially 
common near the settlement on the northwest island and was probably in¬ 
troduced as a lawn grass. Two native grasses occur on the island: Eragrost 
whitneyi and Lepturus repens . The Lepturus is a common groundcover under 
the Cocos groves, along paths and near the lagoon in openings with sandy 
soil”! Many clumps in the latter situation were observed with stolons and 
many areas appeared to have derived their covering of this species from one 
initial clump. Eragrostis whitneyi was found growing in sand in a lagoon 
side depression on the northeast island. It was plentiful locally but >ras 
not discovered on the other two large islets after a careful search. This 
distribution is curious in light of the fact that so much of the peripheral 
areas of the larger islets of the atoll are suitable to this species, 
Another striking instance of the local distribution of this species was 
found on Sydney Island in the Phoenix Group confined to saline encrusted 
sandspits of the central lagoon not more than 2.8 dm. above the water level 
of the lagoon and in association with Sesuvium portulacastrum . It appeared 
that these small spits had been inundated by waves carrying a saline froth. 
Salt encrusted both species of plants and the Eragrostis was found in many 
instances encrusted with a layer of dried salt and algal debris. To date 
this unique species has been found in the Phoenix, Line and Hawaiian Leeward 
Islands. One collection is also extant from Onotoa in the Gilbert Islands. 
