399 
tivity may be present in all, but it is decidedly much more in evidence 
throughout the entire length of the wet season. During 3 or 4 months 
bamboo culms reach a height of from 12 to 15 meters, the shoots of 
trees develop rapidly, and herbaceous vegetation springs up with sur- 
prising quickness, the change from the dry to the wet season resembling 
to some extent the spring activity of vegetation in temperate regions. 
Aside from the clothing of the trees with their full quota of leaves, 
the appearance of numerous herbs of various kinds decidedly changes 
the aspect of the vegetation. However, it is strikingly true that almost 
no herbs appear in the dense parang growth or in the bamboo forests, 
save here and there a few ferns, but on the edges of the clearings, 
in cogonales and, indeed, in any place where the vegetation is sufti- 
ciently thin to admit light to the ground, the latter is soon covered with 
various herbs. Among these, weeds such as Hyptis, Triumfetta, Adenos- 
temma, ete. (see p. 396), are apt to form thickets on the edge of cogonales, 
where the shade of the surrounding tree vegetation is too great for the 
grasses. Among the first geophilous herbs is Amorphophallus campanu- 
latus. About the middle of May, in places, in the thinner parts of the 
parang this species develops from a spherical corm, 15 to 20 centimeters 
in diameter, to an inflated spathe as large as one’s head. Soon after the 
flower dies, a three-parted leaf with the segments pinnatified and with 
a spotted petiole appears. Often this reaches the height of 2 meters 
and is strikingly prominent in contrast with the surrounding vegetation. 
About the same time the flowers of Curcuma zedoaria and Zingiber 
zerumbet become apparent, to be followed by colonies of the canna-like 
leaves of the Curcwma and the pinnate ones of Zingiber. These are the 
most prominent of the geophilous herbs which frequently occupy large 
patches to the exclusion of all others. Cogonals which are brown in the 
dry season, rapidly turn green during the wet one, and in places where 
the grass is thin, many herbaceous plants or seedlings of arboreal 
species appear. In July, colonies of Ophioglossum nudicaule, or single 
individuals of Helminthostachys zeylanica among the ferms, grow in 
half open places on the edges of the parang or of the bamboo. By 
September these have disappeared. Prominent ferns, all but geophilous 
during the dry season, are Hemionitis arifolia, H. gymnopterodea, Gym- 
nopteris taccifolia, Polybotria apiifolia and Adiantum philippense. 
Cheilanthes tenuifolia is xerophytic and tropophilous. Anthoceros gran- 
dis of the liverworts, prominent during the wet season on moist banks, 
and a few mosses are all which were noted of the Bryophytes. 
Epiphytes—The epiphytic vegetation, although not well studied, 
shows a scarcity of species in comparison with the formations higher up 
* However, it must not be overlooked that many trees show vegetative as well 
as reproductive activity during the period of low chresard. This is especially 
the case with plants growing on the edges of water courses, where the chresard is 
more uniform throughout the year. 
