16 VARIATION, DISTRIBUTION, AND EVOLUTION OF THE GENUS PARTULA. 
the forest flora of Guam than that of Safford (oc. cit., pp. 55, 56), which is herewith 
quoted with minor elisions: 
The forest vegetation of Guam . . . consists almost entirely of strand trees, 
epiphytal ferns, lianas, and a few undershrubs. The majority of the species are included 
in what Schimper has called the Barringtonia Formation. The principal trees are the 
wild bread-fruit, 4rtocarpus communis; the Indian almond, Terminalia catappa; jack- 
in-the-box, Hernandia peltata; the giant banyan, . . . (Ficus sp.); two other species of 
Ficus, . . . 3 Pandanus fragrans . . . and Pandanus dubius, two screw-pines which 
differ from many of their congeners in not being found growing on the outer beach; Ca/o- 
phyllum inophyllum, a handsome tree known in the East Indies as Alexandrian laurel . . ; 
Barringtonia racemosa, which, unlike its congener, B. speciosa, leaves the coast and fol- 
lows along the streams into the interior; Heritiera littoralis . . . called in India the 
looking-glass tree . . . ; and, among recently introduced trees, Canangium odoratum, 
the fragrant. flowers of which are the source of the perfume known as the ilangilang, 
Annona reticulata, the custard apple or bullock’s heart, and Pithecolobium dulce, a legu- 
minous tree known in the East Indies as the Manila tamarind . . . No truly indig- 
enous palms occur, but 4reca cathuca, the betel-nut palm, grows spontaneously in damp 
places; a small slender-stemmed species allied to Areca . . . is gradually spreading 
over the island; and the Caroline Island “‘sago-palm,” Celoccocus amicarum, has been 
introduced sparingly. Those familiar with the forest vegetation of Eastern Polynesia 
will be struck by the absence from the forests of Guam of such genera as Freycinetia, 
Papyrius (Broussonetia), Urticastrium (Laportea), Myristica, Parinari, Bocoa (Ino- 
carpus), Dysoxylum, Nyalelia (Aglaia), Macaranga, Bischofia, Aleurites, Omolanthus, 
Spondias, Rhus, Alphitonia, Melochia, Kleinhovia, Metrosideros, Mesa, and Diospyros. 
Among the climbing plants and epiphytes of the forest are Lens phaseoloides, the 
scimitar-pod sea bean . . .; Stizolobium giganteum . . . ;aspeciesof Calamus . . ; 
Luisia teretifolia, an inconspicuous orchid, and the minute leafless Taeniophyllum fasciola; 
Dischidia puberula, an interesting asclepiad growing upon trees . . . ; bird’s-nest 
ferns (Neottopteris nidus), perched on the branches associated with broad ribbons of 
Ophioderma pendula, tufts of Nephrolepis acuta and N. hirsutula, grass-like Vittaria elon- 
gata, and pendent tassels of Lycopodium phlegmaria . . . ; climbing leathery-fronded 
Phymatodes phymatodes, \obed like oak leaves; Cyclophorus adnascens, with linear-lanceo- 
late fronds; graceful Davallia solida . . . Tith glossy divided fronds, and the interesting 
Humata heterophylla . . . 
Beneath the shade of the forest trees several undershrubs are usually found, including © 
species of Icacorea, Piper, Peperomia, and the creeping rubiaceous Carinta herbacea . 
On the edges of the woods and by the roadsides are thickets of the spiny Gui/andina crista 
. Lemoncito thickets (Triphasia trifoliata) are also common, the bushes sprouting 
from the roots and bearing fragrant, white, jasmine-like flowers and scarlet berries 
resembling miniature oranges. Among the succulent plants are wild ginger (Zinziber 
zerumbet), turmeric (Curcuma longa), Canna indica, the Polynesian arrowroot (Tacca 
pinnatifida), and the introduced Tetsia terminalis, a liliaceous plant with graceful tufts 
of red leaves. Besides the climbing and epiphytal ferns already mentioned there are 
many others growing on the ground, including Be/visia spicata, Dryopteris dissecta, Dryop- 
teris parasitica, Asplenium laserpitiifolium, A. nitidum, Microsorium irzoides, and several 
species of Pteris. No filmy ferns (Hymenophyllaceze) have been found on the island. 
The only tree fern of Guam thus far known is A/sophila haenkei, growing in damp places 
and often associated with Angiopteris evecta. 
Cycas circinalts is also a striking and important element of the forest associa- 
tion; it thrives abundantly in the bush of the northern plateau and somewhat locally 
