1914] CHASE— CLIMBING BAMBOOS 279 



Spikelets sessile, 12-20 mm. long, slender, the slender, clavate 

 rachilla joints zigzag, 3-5 mm. long; glumes 3 or 4, approximate 

 (the lower internodes of the rachilla about 0.1 mm.), the strong 

 midnerves hispidulous toward the summit, the lowermost glume 

 acuminate or setaceous, 2.$-$ mm. long, the uppermost acute, 

 4-4.5 mm - l° n g> about equaling the rachilla joint; florets 2 or 3, 

 nearly terete, 6-8 mm. long, distant, one-third to one-quarter 

 longer than their rachilla joints; lemma lanceolate, acuminate, 

 pubescent, with three strong nerves and one or two pairs of faint 

 intermediate nerves; palea membranaceous, slightly shorter than 

 its lemma, broad, obtuse, deeply folded between the ciliate keels; 

 stamens 3; stigmas 2, plumose. 



From my observations, I think this species forms an exception 

 in the bamboos in that the culms are not perennial but herbaceous, 

 dying down each year. When first seen along the Rio Maricao, the 

 middle of October, there were numerous young culms, from a foot 

 or two to six or eight feet long, crawling on the ground or beginning 

 to climb. Hanging in the trees overhead were quantities of frayed 

 dead stems falling to pieces when touched. By the last of Decem- 

 ber this species was high in the trees and hanging down like the 

 other two species. There are no strong culms as in other bamboos 

 or in Lasiacis; the largest found is but 3 mm. in diameter. The 

 culms are not more woody in texture than are those of some of our 

 species of Panicum or Andropogon. Since there is neither winter 

 nor dry season, there seems to be no reason why the plants should 

 die down, but apparently they do die down like ordinary grasses 

 that are perennial by underground parts only. It is a most airy, 

 graceful, delicately beautiful species, the long, slender, vinelike 

 culms with their clusters of pale green foliage festooning the trees 

 or hanging free from the long limbs above a trail or rivulet and 

 suggesting a lacy veil. The foliage becomes glaucous in drying, 

 but in the growing plants is a light but not grayish green. 



Bureau of Plant Industry 

 Washington, D.C. 



EXPLANATION OF PLATE XXI 



Arthrostylidium sarmentosum Pilg.: a, portion of culm with inflorescence, 

 X£; b, spikelet with portion of rachilla, X3. 



