218 BULLETIN : MUSEUM OF COMPAKATIVE ZOOLOGY. 



dantly, and the narrow band separating Castle Harbor from Harrington 

 Sound is comparatively well wooded (Plate YI.). Though there has been 

 over that district a greater denudation, judging from the general appear- 

 ance of the outcrops of isolated patches of weathered seolian rocks, which 

 form here and there low vertical cliffs. 



The hills to the eastward of the flats extending on the north shore to 

 St. George Island and the islands protecting the entrance of the harbor 

 are comparatively bare of vegetation. The few stunted cedars and other 

 bushes growing on the north side of that part of the Bermudas ai'e mainly 

 limited to the southern slopes. In fact, all the eastern part of the Ber- 

 mudas, including the territory around Harrington Sound, shows far 

 more than the central part of the principal island the effect of denudation 

 which has taken place both there and in the western district of the 

 group. The aeolian rocks crop out in all directions, greatly weathered, 

 and are near the surface changed to hard ringing limestone. 



Toward the summits of the hills and in the saddles passing into the 

 interior of the main island the cedars are more abundant, and in the 

 lower and better watered valleys palmettos grow in small groves, form- 

 ing the same contrast with the Bermuda cedars which they do in 

 similar localities with the pines in the Bahamas. In all directions the 

 wild verbena is to be found, either as the only growth in the more bar- 

 ren districts, or encroaching to a great extent on the open spaces of the 

 wooded parts of the islands. In the valleys and lowlands of the islands, 

 the soil is sometimes of considerable thickness. This is especially the 

 case in the series of longitudinal sinks parallel with the south shore, 

 which extend from Hungry Bay through the greater part of Devon. 



At the western as at the eastern extremity of the islands we find a 

 similar diminution in the vegetation. The southwest end of Somerset 

 Island is bare, and the surface greatly worn. On the rest of the island 

 there are fewer junipers than on the main island, and they are smaller 

 and more scattered, as they are on the east end of the main island 

 all the way from Wreck Point to High Point. 



The difference in the aspect of the Bermudas and Bahamas is per- 

 haps due to the prevalence of the trade winds in the latter, where they 

 have had the tendency to build sand dunes bearing in one direction, their 

 sea slope being abrupt, while the bank slope is more gentle, thus forming 

 long lines of dunes lapping and running in one direction. This leaves 

 long, narrow valleys between the ranges of dunes, and, as is well seen at 

 Nassau and Andros, produces a greater monotony in the outlines of the 

 islands as compared with the varied landscape of Bermuda. These valleys 



