70 Geology of St. Croix. : 
of limestone, in which were imbedded the leaves and trunks of 
dicotyledonous plants. ‘They were both converted into the sub- 
stance of the rock, but were well preserved. ‘The largest speci- 
mens of wood I obtained were about four inches in diameter; 
though, if I am not mistaken, I saw the impressions of those 
much larger. 'The cortical layers were very distinct, and, through 
_the smaller pieces, were holes, which the pith of the plant once 
obviously occupied. The bed which contains them is of limited 
extent. It was clearly raised with the formation in which it is 
implicated ; and, if they are both contemporaneous, the clay form- 
ation is obviously of recent origin. I am in doubt, however, 
whether this bed is not the remnant of a calcareous stratum, 
‘which may have covered the whole of this formation when it 
was raised, but has since been removed by meteoric agents. If 
this supposition is true, other beds will probably be found, from 
which farther light may be obtained. I may also add, that just 
before leaving the island, I received some specimens of | ne, 
containing casts of corals and marine shells,- taken from 
which was said to be found in this formation near Judith’s Paneg 
I would especially recommend this locality to the attention of any 
one who may hereafter have an opportunity to examine the geol- 
osy of the island. 
It may not be improper to remark, that this Sumnasians is exceed- 
ingly well-developed at St. Thomas, an island about forty miles 
north, which bears a strong resemblance in its geological .char- 
acter to that part of Santa Cruz which I have just described. 
The columnar and trappean forms of the rock, imperceptibly 
graduating into regular schistose strata, are, perhaps, more com- 
mon. ‘This island, also, contains extensive localities of trap and 
porphyry. On the west side of the harbor, they are seen 
truded among and overlying stratified and altered rocks, where 
the peculiar globular concretions of the trap are very apparent in 
the decomposing surfaces of large insulated masses. The clay 
and the trap are the only two formations of this island. Of the 
corresponding groups of Antigua, [ intend to speak at another 
time. I will only add here, that indurated clay constitutes a dis- 
trict of enedemnble extent on the island of Barbadoes. I saw it 
= ieione aay College, where it is not fully developed, and 
sfore speak of it with confidence. Here it was more 
cacane: semhandanred than the rocks of which I have 
