AGASSIZ: BAHAMAS. 



vertical cliffs of about eighteeu inches in height, presenting all the 

 appearances of water action so characteristic of the higher limestone 

 clifts on other islands of the Bahamas. The diminutive seas had eaten 

 out small bays, formed promontories, and indented the coast in a man- 



TOUNG MANGROVES, WIDE OPENING. 



ner no less characteristic tlian the shore lines of higher islands when 

 exposed to the full action of the trades. Masses of dead shells are found 

 blown up or thrown up on the diminutive beaches of the recesses cut out of 

 the shore line. Billy and Williams Islands must at one time have formed 

 a part of the northwestern extension of Andros. There is no part of the 

 Bahama Bank which is so instructive as that now occupied by Andros. 

 Nowhere else do we find so large an island undergoinij; all the processes 

 of disintegration, division, and ernsinn wliich have on other parts of the 

 bank ended in forming the submarine shoals, and leaving liere and there 

 traces of the former extension of the larger islands of which tlie bank 

 was composed. Andros still occupies a romparativoly large part of the 

 Great P)ahama Bank to the west of the Tongue of the Ocean ; yet it is 

 cut into three islands by the so called bights wliicli connect the Tongue 

 of the Ocean with the shallow waters of the bank to the westward of 

 Andros. Its former soutlicrn extension is marked by tlie numerous 

 small islands, isolated rocks, sand banks, and ridges reaching southward 

 and eastward from the southern end of Andros. Its former western 



