124 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



These three formations, although distinct in lithologic characters, 

 grade into one another, the Richmond being a littoral, non-calcareous 

 clastic formation, the Cambridge a mixed calcareous and argillaceous 

 littoral, and the Montpelier a truly deep sea foraminiferal chalk deposit. 



Do la Beche, the earliest writer on the geology of Jamaica, placed 

 the beds included in our Richmond beds, in his medial, or Carboniferous 

 Series,^ and included the Cambridge in the base of his " White Lime- 

 stone," now known to embrace formations from Eocene to recent inclu- 

 sive, the Miocene excepted. He referred the fossils from the base of 

 this series (our Cambridge beds) to the Eocene, and considered them to 

 *' belong to tlie same age as the London Clay, Calcai?'e grassier of the 

 Paris Basin," and published a figure of one of the large Cerithiums^ 

 peculiar to it. 



Duncan and Wall, and others connected with writing up the Ja- 

 maican Reports, referred the beds of our Richmond formation to the 

 Eocene, but expressed many confusing opinions concerning the age of 

 the beds we have placed in the Cambridge and Montpelier, some of the 

 writers having referred them at first to the Eocene, — which conclusion 

 was finally abandoned by Etheridge and others, who confused them with 

 the Miocene strata. These beds, which underlie the white limestones, 

 were at first considered Eocene by C. B. Brown and other field workers 

 in the western parishes, but through the unfortunate miscorrelation on 

 the part of the workers in the eastern parishes, as explained in the In- 

 troduction of this Report, they were confused with the Bowden beds, 

 which overlie the white limestones, and all conception of their true 

 position was completely obliterated. 



C. B. Brown ^ described the Yellow Limestones (Cambridge beds) with 

 Orbitoidcs in St. James, " which agrees with descriptions of Claiborne, 

 Jackson, and Suggsville beds." He noted that no provision had been 

 made by the government for a critical examination by a paleontologist; 

 " therefore until such has been made, the suV)jcct must remain unset- 

 tled." He also referred to a list of fossils from this formation in the 

 Appendix of the Report, but docs not give it. It is a singular fact that 

 the species of this fauna were apparently never seen nor studied by the 

 English paleontologists, into whose hands fell the official collections of 

 the Jamaican Surveys. 



Sawkins's ])ublished views are conflictinir. At one time in discussing: 

 the "Yellow Limestone of Trclawney" (our Cambridge beds), he de- 



1 Tmns. Geol. Soc. London, 1826, No. 30, pp. 157-103. 2 ibid., p. 171. 



* Jamaican Reports, p. 'Jil. 



