00 



It would seem, then, from the foregoing, that in the distribution 

 of the plant groups in this great mountain range, we have not, 

 primarily, a problem of altitude. For the altitude per se can 

 scarcely be of much importance as a determinant, for by it no 

 greatly changed conditions of atmospheric pressure are reached, 

 our greatest elevation being nov/here more than three thousand 

 six hundred feet. It is cooler, however, at the ridge than at the 

 coast and this may have some effect on the precipitation, and, 

 secondarily, of course, on the plants. 



But the Maestra rises more or less abruptly from the level 

 part of Cuba, and furnishes a great barrier of from three to eight 

 thousand feet in height and about sixty miles long. Its altitude 

 thus at once becomes the all-important factor in regulating the 

 amount of rainfall that gets over to the leeward side of the range. 

 This action of the ridge in monopolizing the better part of the 

 moisture from the trade- wind is responsible for the comparative 

 dryness of the whole southern exposure. The division of the 

 area into regions coming under the influence of this wind and 

 those lacking it, is, therefore, not such an arbitrary proceeding 

 as one might suppose who had not seen this marked example of 

 the importance of the rainfall in determining the general charac- 

 teristics of any given area. In the variation of the plant associa- 

 tions cited under the discussion of the southern slope other fac- 

 tors must be taken into consideration. But these are almost 

 wholly local in their effect and are not therefore comparable to a 

 factor of the scope and importance of this trade-wind. 

 New York Botanical Garden. 



A NEW BLACKBERRY FROM THE VICINITY OF 

 PHILADELPHIA AND WASHINGTON 



By William H. Blanchard 



The blackberries in the vicinity of Philadelphia and Washing- 

 ton were studied by the writer in July, 1906. The species found 

 are not numerous. Rubiis hispidiis L. and R. aineifoliiis Pursh 

 occur, but are not common generally, though R. cuneifolins is 



