FIELD NOTES ON THE CLIMBING BAMBOOS OF 



PORTO RICO 



Agnes Chase 



(with plate xxi) 



months 



Porto Rico in the fall of 1913, the writer became acquainted with 

 the habits and field aspect of the beautiful and interesting climbing 

 bamboos of the island. The botanical descriptions published, hav- 

 ing been drawn from herbarium material, fail to give much idea of 

 the appearance of the living plants. 



The climbing bamboos, with the tree ferns and mountain palms, 

 are characteristic of the mountain regions from 2000 feet altitude 

 upward to the summits. At present four species are known: 

 Arthrostylidium multispicatum Pilg., A. sarmentosum Pilg., A. 

 angustifolium Nash, and Chusquea abietifolia Griseb. Sterile plants 

 of the last were collected by Dr. F. L. Stevens and Mr. W. E. Hess 

 on Monte Alegrillo in November 1913, but this species was not 

 found by the writer. The three species of Arthrostylidium have 

 much the same habit, climbing high, repeatedly branching, and in 

 their greatest development swinging down in great curtains from 

 the trees overhanging trails or streamlets. They love the glints of 

 sunlight along the trails or water courses and are very rarely found 

 in deep shade On mature culms two sorts of branches are pro- 

 duced, short leafy ones in whorls at the nodes, and elongated ones 

 which bear whorls of short leafy branches and branch again, the 

 process being repeated until at times a slope for several yards is 

 bound together in a tangled mass. 



Arthrostylidium angustifolium, a species very closely related to 

 the Cuban A. capilli folium Griseb., I found only once near a 

 cataract at some 3000 feet or more in Indiera Fria. This has linear 

 blades, 2 to 4 mm. wide and as much as 30 cm. long, crowded on 

 short sterile branchlets which are arranged in dense whorls at the 

 distant nodes of the slender culms. These culms hang straight 20 

 or 30 feet from trees 40 or 50 feet high, or ft toon themselves over 



277] 



[Botanical Gazette, vol. 58 



