E7 



Vessels (transverse section) fe-.v, mc^erstely l9rp:e, 

 (about ,13 cm. in diameter), romid or ellijitical, open or i 

 sometimes closed with dark brown tyloses, and arranged , 

 chiefly singly, sometimes in small groups or radially in 

 pairs. Vessel walls ( lon^^itudinal section) with numerous, ' 

 large and small bordered pita; pit o^jenings transversely 

 elongated, sometimes united and forming ladder-like -i_j^._;_)ea- 

 rance. In addition to vessels and closely resembling them 

 even under low magnification are resin canals, which are ' 

 surrounded by numerous wood-parenchyma fibers or resin- j 

 secreting cells, jinds cf vessel segments completely ab- i 

 sorbed, wood fibers about 1,69 mra. long with varying j 

 thicicnessea; cell walls of larger fibers ;noderately thin 

 and large cell cavities; small fibers with thick walls and 

 obliterated cell cavities. Wood fibers irregularly arranged 

 and very small fibers scattered in among large ones, ffood- i 

 parenchyma fibers abundant and arranged in tangential lines ] 

 connecting vessels; also grouped among v/cod fibers and ! 

 surrounding all vessels. Pith rays numerous, narrow, barely , 

 visible under hand lens, from 1 to 3 cells wide and from a ! 

 few to 15 or 20 cells high. 



Distribution, common names and u s es 



7/hile in its typical station at Bachelor's Hall, Jamaica, 

 this tree is said to grov; at an altitude of about 200 meters 

 above sea level, it belongs exclusively to the low, perma- 

 nently or temijcratily inundated forests of both the Atlantic i 

 and Pacific watersheds of Panama. In the Chagres basin it i 

 has oeen reported from the mouth of the river to Matachin, a 

 locality presently under water, and in 1914 it was still 

 conspicuous among the live trees of the inundated area, 

 forming extensive groups if the Gatun, Trinidad and Cailo 

 Valleys, In Darien, it is the dominant species of the j 

 valley flats immediately closing upon the tidal belt. The | 

 forests of this section, the soil of which is more or less i 

 covered with fresh water daring the heavy rainy season, are ' 

 known as cativales , on account of the ^jredominance of the ; 

 cativo , this being the native name of the species. These , 

 flat districts are considered as the best for rice cultiva- j 

 tion, prooably on account of their abundant humidity. ' 



\y^ \ \ The hard, heavy wood of the cativo is resinous and diffi- 



V J I cult to work; it is considered as of little or no use 





