HILL: GEOLOGY OF JAMAICA. 131 
the same valley as Catadupa and Cambridge. This is the only Cepha- 
9pod as yet found in Jamaica, and is probably the same form which has 
been teferred to as Aturia zigzag. If its position and determination 
“ould be verified, it would prove another valuable testimonial to the 
“ocene age of the beds, as this form is characteristic of the late Eocene 
of the United States. De la Beche! has noted the occurrence of a 
utilus, probably the same as that previously mentioned from Cuba, 
% Terrebratula, and Nummuline in association with other species near 
Tale Hall House, Clarendon. No other specimens of fossil Cephalo- 
Poda have been found in Jamaica. 
_ OF the fossil Mammalia, only a single fossil trace has been discovered 
n Jamaica, Prorastomus sirenoides Owen,? a species of Sirenia related 
? the Manatees of to-day. This specimen was reported from Freeman’s 
all Estate in the southeastern corner of Trelawney near the centre of 
è island, The locality from which this specimen came is a typical 
"crop of the Cambridge beds as described by Brown,’ and Owen's 
cription of the material in which the specimen was embedded con- 
po also to the lithologic character of that formation. While no final 
Pinion can be expressed without seeing the specimen and locality, 
° evidence certainly points to the early Eocene age of this animal.t 
s E marine animal, its occurrence in the rocks of Jamaica is of 
., gnificance in tracing previous relationships of Jamaica to other 
‘lands, 
Thig fauna of the Cambridge formation is remarkable in several ways. 
a for the peculiar mixture it affords at Catadupa of Eocene and 
Es genera; and secondly, from its collective dissimilarity to 
littoral a known fauna, especially to those of the = continental 
collect formations. When a small apeere trom Cambridge was 
Moto ted by us in 1896 and submitted to a morhaty prleontologiet of 
de d = rejected by him on the ground that K was not of Tertiary 
m Cretaceous, and this too before true Rudistes had been recog- 
an m it. Recognizing its absolute dissimilarity to any known Ameri- 
9taceous fauna, we revisited the region in 1897, and discovered 
Nautilus Cubensis, Lea. Trans. Am. Phil. Soc., 1841, Vol. VII. p. 259. 
1 Mart. Jour. Geol. Soc., 1855, Vol. XI. pp. 541, 543. 
4 amaican Reports, p. 224. 
M n deposits of the Cretaceous and early Eocene periods are recognized all 
the World, but not a trace of the Cetacea and Sirenia have been found in 
~Ma 7 far as known, these types appear fully evolved at the top of tho Eocene. 
' Science, October, 1897, page 228, 
