AuG. 19, 1923 VAUGHAN: STRATIGRAPHY OF THE VIRGIN ISLANDS 309 
Saint Croix 
In Saint Croix Tertiary limestones and marls cover an area reaching 
the southern shore south and southeast of the hills in the northwestern 
part of the island, they extend northward to the north shore just east 
of the mouth of Salt River, whence the eastern boundary runs south- 
ward to the west side of Waiters Point. In general the limestones are 
soft, rather crumbly, and there are interbedded layers of conglomerate. 
The dips are in general southward, at angles ranging from 8° to 15°— 
strongly contrasting with the steep dips, in places 80° or more, of the 
Cretaceous rocks. 
Three horizons seem to be represented in these limestones, viz.,- 
(1) middle Oligocene, (2) probably upper Oligocene, (3) lower Miocene. 
Middle Oligocene 
Station 8649. Two-tenths of a mile southwest of Wheel of Fortune 
estate house; collection made on northern slope of a low hill. 
Foraminifera: 
Rotalia sp. Abundant 
Amphistegina sp. Compare with station 8648. 
Lepidocyclina morgani Lemoine and R. Douvillé. Also Cuba. 
Carpenteria americana Cushman. Also Cuba. 
Madreporaria: 
Astrocoenia decaturensis Vaughan. Also Antigua; Bainbridge, Ga. 
Gomiastrea reussi (Dunean). Also Antigua. 
Cyathomorpha tenuis (Duncan). Also Antigua; Pepino formation of 
Porto Rico; and other places. 
Goniopora microscopica (Duncan). Also Antigua. 
Geologic correlatton.—The organisms from this locality show clearly 
that the geologic horizon is the same as that of the Antigua formation 
of Antigua, for every coral well enough preserved for specific identifi- 
cation also occurs in Antigua, and that it is, therefore, middle Oligocene. 
Probably upper Oligocene 
Station 8647. One and four-tenths sea miles in a straight line 
from Christiansted lighthouse, on the south side of North Shore road 
at Evening Hill. 
This is the locality at which Quin‘ says he found large Foraminifera. 
The rock as exposed in the road is an argillaceous limestone, mostly 
rather soft but there are indurated lumps and beds. The fossils com- 
prise some well preserved nummulitoid Foraminifera and indetermin- 
4 Quin, John T., The building of an island, p. 17, 1907. 
