262 APPENDIX. 



to my doubts, close outside this barrier-like reef, Turneffe, 

 Lighthouse, and Glover reefs are situated, and these have so 

 completely the form of atolls, that if they had occurred in 

 the Pacific, I should not have hesitated to colour them blue. 

 Turneffe Reef seems almost entirely filled up with low mud 

 islets ; and the depth within the other two reefs is only from 

 one to three fathoms. From this circumstance, and from their 

 similarity in form, structure, and relative position, both to the 

 bank called Northern Triangles, on which there is an islet 

 between 70 and 80 feet in height, and to Cozumel Island, the 

 level surface of which is likewise between 70 and 80 feet 

 high, it is probable that the three foregoing banks are the 

 worn-down bases of upheaved shoals, fringed with corals ; left 

 uncoloured. 



In front of the eastern Mosquito coast there are, between 

 lat. 12° and 16°, some extensive banks (already mentioned), 

 with high islands rising from their centres, and others wholly 

 submerged, both kinds being bordered, near their windward 

 margins, by crescent-shaped coral-reefs. But it can hardly 

 be doubted that these banks owe their origin, like the great 

 bank extending from the Mosquito promontory, almost en- 

 tirely to the accumulation of sediment, and not to the growth 

 of corals ; hence I have not coloured them. 



Cayman Island : this island appears in the charts to be 

 fringed ; and Captain B. Allen informs me that reefs extend 

 about a mile from the shore, and have only from 5 to 12 feet 

 of water within them ; coloured red. — Jamaica : judging from 

 the charts, about 15 miles of the S.E. extremity, and about 

 twice that length at the S.W. extremity, and some portions 

 on the S. side near Kingston and Port Royal, are regularly 

 fringed, and are therefore coloured red. From the plans of 

 some harbours on the N. side, parts of the coast appear to be 

 there fringed; but I have not coloured them. — St. Domingo : 

 I have not been able to obtain sufficient information, either 

 from plans of the harbours, or from general charts, to enable 



