HILL: GEOLOGY OF JAMAICA. 83 
having a thickness of 200 feet as measured in the bluff upon which 
Captain Baker's house at Port Morant stands. The loose gravels at the 
base of this section have a very recent appearance, a deception which 
is further aided by the fact that they occur at beach level, and contain 
perfectly preserved fossils resembling modern shells. The fossils here- 
tofore reported from Bowden are found in the gravel bed, and, less 
abundantly, in a few feet of the lower part of the overlying marls, at 
the foot of the hill, at the beginning of the road leading up the hill to 
Captain Baker's, and in such abundance that as many as 400 species of 
Mollusks have been determined by Dr. Dall from two barrels of material 
collected by Messrs. J. B. Henderson, Jr., and C. T. Simpson and the 
Writer. A few specimens occur higher up the hill, while near the summit 
there is a body of firm crystalline secondary limestone containing moulds 
9f the characteristic fauna. The physical characters of this formation 
“an be traced from Bowden to Morant Bay and beyond nearly to Yal- 
labs Island, but there it loses its identity. On the road from Bath to 
Bowden its position above the Cambridge beds is fairly well revealed. 
Tho stratigraphy of the formation has not hitherto been presented 
Correctly, although in the Jamaican Reports under the name of the 
“Yellow Limestone ” it was partially confused with the entirely differ- 
ent beds herein described as the Cambridge formation, and the gravel 
beds were mapped with the Pleistocene and recent formations.) Hence 
lts identity as a formation did not appear in these Reports.? 
It is only on the south coast of the east end of the island that 
® Bowden beds have the characters mentioned. It is evident that 
the formation with modified lithologic features occurs elsewhere on the 
'sland, for the Bowden fossils have been found on the opposite side by 
"8, and reported from round the district of Vere near the coast of 
Clarendon by other writers, in formations of quite a modified lithologic 
tl 
! Careful search of Barrett's writings show that he made two brief references 
these beds, In one place (Jamaiean Reports, page 44) he merely mentions 
eds of marl, sand and conglomerate of the Bowden series," and alludes to sec- 
08 and further descriptions to be given, but which were never published. 
Pon another page (Ibid., pages 45, 46), under the head of “ gravels, clay, and 
Yellow marl," he gives the following account of what we now know as the typical 
Bowden locality: “On the northeastern portion of the Port at Bowden we find 
the Upper beds both thicker and more inclined (10° S. E.) than on the west, and are 
o more fossiliferous. Below the Pteropod marl are beds of the most perfect 
Tertiary shells yet known on the island.” 
The fossils of the Jamaica Survey from Bowden in the Museum at Kingston 
lso labelled the “ Yellow Limestone.” 
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