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184 BULLETIN: MUSEUM OF COMPARATIVE ZOÖLOGY. 
that the medial limestones of my section at the entrance to the great 
amphitheatre of Matanzas is also of this formation.! 
From the numerous paleontological descriptions of Duncan, Gabb, 
Guppy, and others, this formation is the classical ** Miocene " of Haiti and 
San Domingo, although careful search of the writings of all these 
authors fails to reveal any stratigraphic data concerning it other than 
that many of the species came from certain beds near Nivajé. 
There is also reason to believe that the Bowden beds are progressively 
more shallow in nature from Jamaica towards Haiti. Gabb there 
encountered this character of formation in contact with the similar 
appearing Richmond and Cambridge beds, and confused them together, 
— a mistake which has been made by nearly all first workers in regions 
where aggradational terraines of similar composition are in contact with- 
out a conspicuous intervening deposit. Gabb himself notes the dupli- 
cation of sedimentation cycles in succeeding epochs? and these very 
conditions may have confused him in San Domingo, as they have 
others in Jamaica. 
It is probable that they may occur in Antigua and other Windward 
Islands, but exploration has not sufficiently progressed to justify a 
positive opinion. Beds of Antigua which we consider of a later age 
than the Bowden beds of Jamaica, and usually discussed with them 
under the general head of the Miocene by Guppy, Duncan, and others, 
may prove to be identical with the Bowden. In these islands the vast 
formations of sedimentary volcanic tuffs were probably being made 
during this epoch. 
Close studies convince me that these beds are lacking in Darbados, 
their position being occupied in the latter island by the unconformity 
between the oceanic (Montpelier) beds and elevated (Pleistocene) reefs 
during which time land existed there. 
According to Dr. Dall the later or true Miocene is unrepresented in 
the fossil faunas of the West Indies, during which time the island 
areas may have had greater expansion than at present. He refers all 
the formations hitherto called Miocene to the Upper Oligocene. It is 
my opinion that the differentiation of the faunas of these two epochs 
needs much research. In Antigua and Porto Rico undoubted Miocene 
exists. 
Vast aggradational deposits of the Kingston type similarly laid down. 
on pre-eroded troughs, benches, interior basins, or other erosion sur- 
1 Notes on the Geology of the Island of Cuba, Plate I. Fig. 4. 
2 Op. cit., p. 156. 
