364 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1942 



and air currents differ, the bromeliads which have adapted themselves 

 to these changes will be different. 



It was especially interesting to observe the continually changing 

 parade of species during the ascent of Mount Itatiaya, which is 

 nearly 10,000 feet high. At every rise of a few hundred feet, new 

 bromeliads would appear, and then gradually disappear as we reached 

 higher plant strata. And yet one Vriesia and one Aechmea started 

 with us near the bottom and stayed with us until we had almost 

 reached the top. But as w^e passed the tree line, they were 

 left behind, although they attempted to stick it out on the sides of 

 some of the large boulders. At the top, the exposure to wind and 

 cold was too great for them, and they relinquished the territory to 

 the Fernseea itafiaiae, the range of which is restricted to this moun- 

 tain top. It is the sole member of its genus and seems completely 

 satisfied with its isolation. It withstands frost, sun, wind, and 

 drought and requires only the modicum of food that can be obtained 

 from small crevices or cracks in the boulders. 



Aechmea nudicaulis^ on the other hand, has not been satisfied and 

 has wandered all over the American Tropics. We found it in Mexico, 

 Cuba, Trinidad, and Brazil; it is profuse in Central and South 

 America. It lives in trees or on rocks in the coastal area and gen- 

 erally enjoys either sun or shade. With its range extending for 

 thousands of miles, its plant form and its flower do not show as much 

 variation as one would expect. 



On the shadowless sand dunes of the Atlantic coast in the state 

 of Espirito Santo we found another AechTnea as yet not definitely 

 determined but undoubtedly close to A. nudicaulis. It is a stiff, gray- 

 brown, tubular plant, almost metallic in texture. It grew right up 

 to within a few yards of the sandy beach. Almost by its side we 

 found a new Portea with short, stiff 18-inch leaves. This same 

 Portea we found again growing on mangrove trees in a swamp, 

 just a few feet above the water. There its leaves were narrow, limp, 

 and 6 feet long. The stiff Aechmea^ however, refuses to grow rapidly 

 no matter where you place it, and while it does change to a more 

 greenish cast in color in certain locations, its growth still remains 

 slow, stiff, and rough. 



An example of what happens to certain plants if the conditions 

 are changed is found in Billbergia Meyeri^ which I found in palm 

 boots in harsh, dry country on the western border of Sao Paulo, 

 where it was exposed to both extreme drought and torrential rains. 

 We brought some of these plants back with us. Those that I kept 

 in full light and gave no water retained their original shape ; the plants 

 kept in the shade made rapid growth and produced leaves three 

 times their original length. When seeds of this species were planted, 



