156 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



*' 39. Hopewell, lower reef between Lucea and Montego, Jamaica : 

 Meandrina, sp.; Siderastrsea radians, (Pallas) ; Orbicella acropora, (Linn.) ; 

 Porites porites, (Linn.) ; Madrepora muricata, Linn., forma cervicornis, 

 Lam. 



" 50. Soboruco cut in railway, Orange Bay, old Soboruco : Orbicella 

 radiata, (Ell. and Sol.). 



" 54. Soboruco, Eunaway Bay : Orbicella acropora, (Linn.). 



" 71. One mile west of St. Ann Bay; Lower Soboruco : Orbicella 

 acropora, (Linn.) ; Siderastrsea sp. 



" 93. Corals from stratified limestone. Mulatto Bay, (Manchioneal 

 Beds) : Orbicella acropora, (Ell. and Sol.) ; Orbicella radiata, (Ell. and 

 Sol.) ; Meandrina, sp. 



" Manchioneal Bluff, * same as other reefs.' '' 



PART IV. 

 Geologic and Topographic Evolution of the Island. 



In the preceding chapters we have set forth the general geographic 

 features and the details of composition, structure, and paleontology, and 

 arrived at conclusions by whose use the events accompanying the 

 geologic and geographic evolution of the island can be more intelligently 

 reviewed. 



Upon the table (page 143) we have summarized this history in a 

 manner that will enable the reader to follow what will now be set 

 forth in detail. A short sketch of the principal events of its history 

 will now be given, including, first, a brief outline of the events, next, 

 an interpretation of their magnitude. 



The known history of Jamaica begins with the expiring days of the 

 Cretaceous period. What part the present locus of our island played 

 in tlie earlier events of the battle between sea and land preceding this 

 epoch cannot at present be stated, but we do know that in late Creta-' 

 ceous time its crests appeared above the waters, and that in succeeding 

 epochs grew more and more conspicuous. 



The vast accumulation of rolled igneous pebble of hornblende- 

 andesitcs and volcanic tuffs, which constitute the oldest known rocks 

 of Jamaica, prove clearly that in late Cretaceous time volcanic eruptiv- 

 ity was active at or near the island during their formation, while the 

 colonies of peculiar fossils interbedded at intervals in these rocks fix 

 the time of their origin as the latest epochs of the Upper Cretaceous 



