388 TRANSACTIONS OF THE CANADIAN INSTITUTE. [Vou. VIII. 
the numberless varieties and gradations make it difficult to establish. 
well defined species in that genus; and therefore when we come to 
questions of distribution we do not feel the same confidence in dealing 
with them as we do with better defined organisms. But Modosaria 
abysorum has a character which, so far as I am aware, is not found in any 
other nodosaria. Many nodosarians have a spine or mucro at the apex 
or initial segment, and so indeed have some cristelarians and other 
related foraminifera, but none that I know of have more than one apical 
mucro except the one I have just named, and among the numerous 
nodosarias which appear in the Naparima oceanic beds of Trinidad this 
one is always distinguishable by the polymucronate apex. I have discussed 
the subject in the Geological Magazine, 1904, page 246, and need only 
refer to it here as supporting the theory of a connexion between the sea 
in which the oceanic beds of Trinidad were deposited and the Pacific 
Ocean. The only recent specimens of it were found at “Challenger” 
Station 296, south-west of Juan Fernandez, and it is not recorded from 
any other locality either as a living or fossil species, except the oceanic 
beds of Trinidad and the “ Challenger” Station just named. 
Further notes on tertiary fossils of the Caribean. The occurrence of 
Eliipsotdina in numerous individuals and varieties is another characteristic 
of the oceanic rocks of the Caribean region. The range of form of 
this foraminifer is from the original type of the genus &. ed/ipsoides 
Seguenza, in which all the chambers are embraced by the last, which 
alone is visible to the elongate and drawn-out forms exhibiting the 
whole series of chambers or segments, of which my &. subnodosa (figured 
in Proc. Zool. Soc., Lond., 1894) isan example. The genus seems to be 
abundant in the tertiaries of Italy and occurs also in Fiji and the 
Solomon Islands. &. ellipsotdes and E. exponens have been found in the 
oceanic rocks of Barbados and Trinidad, and in the latter occur also &. 
subnodosa and a number of intermediate and allied forms. I now record 
E. ellipsoides and E. subnodosa from Jamaica. 
The species of foraminifera I have just particularly dealt with are all 
remarkable and very distinct species and not mere varieties. They are 
such as could not have originated independently in different localities, 
and their occurrence in different regions can only be explained by 
migration. None of them are now living in the West Indies, but they 
occur in the Pacific, and El/psozdina is not known in the recent state. 
The conclusion seems irresistible that there was formerly a free communi- 
cation between the Caribean region and the Pacific, and that the 
