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 limestone, 

 containing casts of corals and marine shells, taken from a bed, 

 which was said to be found in this formation near Judith's Fancy. 

 I would especially recommend this locality to the attention of any 

 one who may hereafter have an opportunity to examine the geol- 

 ogy of the island. 



It may not be improper to remark, that this formation 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 pro- 

 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, I intend to speak at another 

 time. I will only add here, that indurated clay constitutes a dis- 

 trict of considerable extent on the island of Barbadoes. I saw it 

 near Codrington College, where it is not fully developed, and 

 cannot therefore speak of it with confidence. Here it was more 

 aluminous and less indurated than the rocks of which I have 



