THE FERN BULLETIN 



85 



Pacific, even the moist forest belts of the volcanoes 

 Fuego and Agua having none so far as known. 



In Mexico, also, as might be expected, tree ferns 

 are wanting from the interior arid high plateau region 

 whose flora has been so thoroughly investigated dur- 

 ing the past 35 years. Upwards of 20 species of 

 Cyatheaceae are known from Mexico, but almost the 

 only recent material of these is that secured upon oc- 

 casional excursions from the table land into the moist 

 lower regions bordering the ticrra caliente of Vera 

 Cruz. 



In the several regions mentioned a few tree ferns 

 are found to be partial to the lowlands. Among the 

 West Indian species of this class may be noted Cyathea 

 arborea, which, however, as already explained, ex- 

 ceptionally occurs high up on the southern slopes of 

 the Sierra Maestra finding there congenial surround- 

 ings which are wanting at a lower altitude in this re-* 

 o-ion. Upon the continent, Alsophila microdonta is 

 found near sea level from Mexico along the Atlantic 

 to South America. Alsophila myosuroides shows a 

 similar preference for low altitudes, its known range 

 extending on the mainland from Vera Cruz to Hon- 

 duras and including also, Cuba and the Isle of Pines. 

 Another very remarkable species of Alsophila (A. 

 Blechnoides) ranges along the Atlantic coast from 

 Guatemala to Trinidad. 



Certain tree ferns occur tvpically as undergrowth in 

 the dense shade of lofty forest trees; for example 

 Cyathea gracilis., a lamacian species which grows ns- 

 u^llv in oeaty soil in wet. sheltered depressions. The 

 trunks of this, t^oueh commonly short, sometimes reach 

 S to 12 feet, whereupon, according to Jenman they 



