ARBORESCENT FERNS. 
277 
most excited our attention were the dragon’s blood (Croton 
Bangui fluuin), the purple-brown juice of which flows down a 
whitish bark ; the calahuala fern, different from that of Peru, 
but almost equally medicinal;* and the palm-trees, irasse, 
macanilla, corozo, and praga.f The last yields a very 
savoury pahn-cabbage, which we had sometimes eaten at the 
convent of Caripe. These palms with pinnated and thorny 
leaves formed a pleasing contrast to the fern-trees. One of 
the latter, the Cyathea speciosa,j grows to the height of 
more than thirty -five feet, a prodigious size for plants of this 
family. We discovered here, and in the valley of Caripe, 
five new kinds of arborescent ferns. § In the time of Lin- 
naeus, botanists knew no more than four on both continents. 
We observed that the fern-trees are in general much 
more rare than the palm-trees. Nature has confined them 
to temperate, moist, and shady places. They shun the direct 
rays of the sun, and while the pumos, the corypha of the 
steppes and other palms of America, flourish on the barren 
and burning plains, these ferns with arborescent trunks, 
which at a distance look like palm-trees, preserve the cha- 
racter and habits of cryptogamous plants. They love soli- 
tary places, little light, moist, temperate and stagnant air. 
If they sometimes descend towards the sea-coast, it is only 
under cover of a thick shade. The old trunks of the cyathea 
and the meniscium are covered with a carbonaceous powder, 
which, probably being deprived of hydrogen, has a metallic 
lustre like plumbago. No other plant presents this pheno- 
* The calahuala of Caripe is the Polypodium crassifolium ; that of 
Peru, the use of which lias been so much extended by Messrs. Ruiz and 
Pavon, comes from the Aspidium coriaoeum, Willd. (Tectaria calahuala, 
Cav.) In commerce the diaphoretic roots of the Polypodium crassi- 
folium, and of the Acrostichum huascaro, are mixed with those of the 
calahuala or Aspidium coriaceum. 
+ Aiphanes praga. 
+ Possibly a liemitelia of Robert Brown. The trunk alone is from 22 to 
24 feet long. This and the Cyathea excelsa of she Mauritius, are 
the most majestic of all the fern -trees described by botanists. The total 
number of these gigantic cryptogamous plants amounts at present to 25 
species, that of the palm-trees to 80. With the cyathea grow, on the 
mountain of Santa Maria, Rhexia juniperina, Chiococca racemosa, and 
Commelina spicata. 
§ Meniscium arborescens, Aspidium caducmn, A. rostratum, Cyathea 
villosa, and C. speciosa. 
