1957] 



THE BOTANY OF THE GUAYANA HIGHLAND— PART II 



283 



the summit of Cerro de la Neblina, Rio Yatua, Amazonas, Venezuela, January 15, 

 1954, New York Botanical Garden. The collectors report that the plants were 

 abundant, forming cushions, but had only old flowers on that date. 



BROMELIACEAE 7 



The relationship of the Bromeliaceae to the area of the Guayana Highland is a 

 curiously exact one so far as present records show. All but three genera, Lind- 

 mania, Broccbinia, and Navia, are very poorly represented if * at all. Lindmania 

 is found in southern Mexico and Central America and in the southern Andes and 

 has a very close relative, Cottendorfia t in northeastern Brazil. As yet there is 

 no authentic record of Lindmania from Colombia, so that its range consists of 

 three widely separated areas with no single species occurring in more than one 

 area. 



Further the Lindmania species of the Guayana Highland comprise 16 of the 

 total 29 and are readily distinguishable from the others by the combination of 

 firm leaves and bipinnate inflorescences. Because of its consistently superior 

 ovary and appendaged seeds Lindmania appears to be more primitive than Broc- 

 chinia and Navia, and I believe that it is ancestral to them. 



Broccbinia and Navia are nearly perfect for a definition of the Guayana High- 

 land area. They were both discovered in 1820 by Martius at Araracoara in south- 

 eastern Colombia, which is at one end of the area, and Navia extends to Tafelberg 

 in Suriname at the eastern end. Species of one or both of them have been found 

 at nearly every point of exploration in the area, but as yet none have been dis- 

 covered outside it. 



Broccbinia has differentiated from Lindmania by the development of a largely 

 inferior ovary and increase in overall size while retaining the bicaudate seed- 

 appendage. Some of its species show a very wide distribution within the area. 



Navia like the dodo has lost its wings and consequently tends to have much 

 more closely endemic species than the other two genera. Most of its species, 

 however, have retained the superior ovary of Lindmania, Both Broccbinia and 

 Navia differ from the remainder of the family in their cochlear sepals, but an oc- 

 casional flower with this imbrication is found in Lindmania. 



Lindmania 



(Key to the species of the Guayana Highland) 



1. Scape evident; axis of the inflorescence evident. 

 2. Flowering shoot over 13 cm long. 



3. Inflorescence lax, but its branches often dense. 



4. Branches of the inflorescence well developed; flowers not fasciculate. 



5. Leaf-blades serrulate throughout; sepals serrulate. 1. L. serrulata. 



5. Leaf-blades serrulate only near base or entire. 



6. Pedicels 10-15 mm long, subfiliform; branches laxly many-flowered. 



2. L. wurdackii. 



6. Pedicels 2-7 mm long, stouter. 



7. Branches of the inflorescence 9-25 cm long. 



8. Scape-bracts exceeding all or all but the highest internodes. 

 9. Leaf-blades vestite on at least one side. 



10. Indument on the upper side of the leaf-blade. 3. L. paludosa. 

 10. Indument on the lower side of the leaf-blade. 

 11. Racemes dense; leaf-blades 40 mm wide. 



4. L. cylindrostachy a. 



11. Racemes lax; leaf-blades 15 mm wide. 5. L. argentea. 



7 By Lyman B. Smith. Illustrated by Robert J. Downs. 



