152 BULLETIN: MUSEUM OF COMPARATIVE ZOÖLOGY. 
the following fossil species from the beds at Bowden: Neocyclotus (Pty: 
chocochlis) bakeri, Simpson ; Lucidella costata, Simpson ; Pleurodonte 
bowdeniana, Simpson ; Thysanophora; Opeas ; Succinea. 
In the marginal land derived material of the upper part of the Blue 
Mountain Series and Cambridge beds, no remains of land or fresh water 
mollusca have been found, and if they existed in late Cretaceous OY 
early Eocene times, it is singular that no trace of them can be found 
in beds so peculiarly adapted for their occurrence. Even if they pre 
viously existed, their absence in the deep water marine beds of the 
Montpelier and Moneague beds would be natural, for they are never 
met with in such formations. 
In the Bowden series, however, land shells do appear for tho first 
time, several species having been sorted out of the great fauna of Fo 
raminifera, Bryozoa, Hydroids, corals, and Mollusca of this peculiar lit- 
toral formation which occurs in the midst of the great White Limestone 
Series. Their appearance here fits in beautifully with the facts of the 
Mid-Tertiary land expansion elsewhere given, and thoroughly satisfies 
the facts of the present known distribution of their descendants in other 
islands and in Central America, as elsewhere explained. | Simpson has 
found a probably fossil land shell in the succeeding Cobre limestone 
of Bog Walk. 
A few traces of fish teeth have been found in the Bowden formations. 
In résumé, it can be said that the Bowden fauna as a whole marks 
a most important horizon in Jamaican history, representing the reap” 
pearance of molluscan life after the long hiatus intervening since the 
Cambridge epoch, and presents the beginnings of the littoral faura 
which have since prevailed around the border of Jamaica in the later 
Tertiary, Miocene, and Pliocene-Pleistocene, and recent time, 
The Cobre Beds. — The Cobre (White Limestone) which may be % 
synchronous but deeper water. formation than the Bowden beds, is 
largely composed of Foraminifera mixed rarely with débris of Mollusks, 
simple corals and Echinoidea. Mollusca are almost entirely missing 
from this formation, except at its immediate base near Bog Walk villag® 
where many imperfect casts may be found, all of which haye a super” 
ficial resemblance to tho Bowden and later forms. In these beds ” 
found two or three speeimens of Echini. The main portion of this 
limestone is almost entirely foraminiferal. 
Our microscopic sections of the white limestone of this formation, from 
the convict quarry east of Kingston and Bog Walk, show a large num“ 
ber of small Foraminifera of many species, but in which Nummulin® 
