508 a T. Trechmann— 



Palaeontology of the Baerettia Bed. 

 The following is the list of fossils found up to the present 

 in this bed : — 



Barrettia cf. monilifera Woodward. 



„ cf. multilirata Whitfield. 



„ „ var. cylindrica nov. 



,, „ var. conica nov. 



Radiolites (Lapeiroiisia) nicholasi A\'Tiitfield. 

 CapTinajamaicensis^hxtfialdi. Upper valve of a small specimen^ 



25 mm. wide. 

 Caprinella (?) sp. Curved upper valve badly preserved. 

 Radiolites sp. Sections in the hard limestone. 

 Ostrea sp. Small species adhering to the Barrettias. 

 Chama sp. A right valve rather like Ck. haueri Zittel of the- 



Gosau beds. 

 Lima sp. 



Cardita (Venericardia) cf. suhcomplanata d'i\.rchiac. 

 Avellana (Eriptycha ?) cf. decuriata Zekeli. 

 Echinoid, probably a new genus allied to Lanieria. 

 Foraminifer. A lenticular form in shape like Grbitoides, measuring; 



up to 6 mm. in diameter. Professor Doxiville assures me that 



the internal structure is not that of Orhitoides} 

 Sponge ?^ A large irregularly cylindrical object about a foot long, 



possibly a calcareous sponge, but the structure obscured by 



recry stall ization . 



Notes on the Fossils. 



The intention of this paper is rather to record the conditions of 

 occurrence of Barrettia in Jamaica than to enter into questions of the 

 morphology or evolution of the organism, a matter which would 

 require much slicing and polishing of specimens for which I have 

 no time at present. There are one or two features, however, to which 

 I should like to draw attention. One of these is the upper valve or 

 lid, which has hitherto never been seen in a satisfactory state of 

 preservation. Barrett's original specimen in the British Museunx 

 has the lid in place, but the decoration of its surface is all but 

 obliterated. Among the yam-fields at Haughton Hall several 

 examples of Barrettia occurred, showing the surface of the upper 

 valve in more or less perfect preservation. I am illustrating some 

 of these, hoping they will prove of use in fixing further the affinities 

 of this peculiar fossil. 



The top valve of Barrettia is, in comparison with the size and 

 massiveness of the lower valve, a remarkably thin and fragile 

 structure, and instead of being definitely flat, concave, or convex, 

 as in the case of most Hippurites, it is in many specimens curiously 



^ I await with interest Professor Douville's report on this and other Jamaican, 

 foraminifera. 



