AGASSIZ: BAHAMAS. 47 



masses are hurled inland and deposited far above the ordinary high- 

 water mark. All the way along the sea face of Long Island we passed 

 large masses of gulf-weed, many of these patches more than twice the 

 size of the yacht. 



The difference in the aspect of the vertical cliffs in different parts of 

 the Bahamas is very marked. If formed at the base of the gentle wind- 

 ward slope of the asolian hills, they are low and of very uniform height, 

 especially if that face is the bank face of the island ; but where the lee 

 face of the hills — lee wlien formed — is also the sea face, the cliffs 

 are on the steeper slope of the teolian hills, are far more irregular, and 

 their height varies greatly, according to the height of the hill which 

 is attacked and the distance inland to which the action of the sea has 

 reached. 



The corals do not form a regular reef off the east face of Long Island. 



The Exuma Islands. 



Plate X. Fig. 5 ; Plate XI. Fig. 1. 



To the west of Cape Santa Maria, Long Island has disappeared, leav- 

 ing only a shallow bank flanking it for its whole length and connecting it 

 with the Exuma Islands. From the central part of the western line of 

 these islands extends a long, narrow spit, the only mark of the former 

 extension of Long Island in that direction. It must have been a con- 

 tinuous shore, forming a great curve, indicated now by the row of islets 

 and rocks which flank that part of the bank, extending in an unbroken 

 line to Flamingo Cay, and from there by Seal Cay and the islets run- 

 ning to the north of Columbus Bank from the Ragged Cays as far as 

 Nurse Channel. 



Great Exuma is the largest fragment remaining of the land which once 

 formed the eastern edge of the bank flanking the west side of Exuma 

 Sound. Like the many islands, islets, and rocks extending northward as 

 far as Ship Channel, it is built up of aeolian rocks. Georgetown, the prin- 

 cipal port of Exuma, lies upon a long inland sound studded with islands, 

 and sheltered from the outer sound by a series of low outlying islands 

 which form a barrier against the force of the trade swell, which gains 

 considerable force over the forty miles or more of sea-way from the east- 

 ern side of Exuma Sound. These outlying islands are themselves gradu- 

 ally being eaten away, and were once also a part of the greater Exuma 

 land, which has little by little become dismembered by the action of the 

 sea upon the subsiding seolian hills. In the inner sound, which extends 



