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LETTER XIX. 
CAP ENCRINITE OF DERBYSHIRE, AND, PERHAPS, OF YORKSHIRE....- 
SUPERIOR TERMINATION SUPPOSED INFERIOR TERMINATION 
TURBAN ENCRINITE OF SHROPSHIRE PELVIS DESCRIBED 
INFERIOR EXTREMITY PECULIARITY OF ITS TRUNK SAME 
COLUMN FROM GOTHLAND. 
The species of encrinus to which I shall now lead your attention, 
is one which, although its remains are most extraordinarily abundant 
in our own country, its history is, perhaps, least of all known to us. 
Indeed we at present know little more of it than that the petrified 
remains of its vertebral column, either in detached pieces, or agglutinated 
together in masses of limestone or marble, have long been found in 
quarries of an immense extent in some of the northern counties of this 
island. i 
Mr. Da Costa remarks that the whole metallic tract of the 
county of Derby is, as it were, one continued quarry of this 
marble; most of the strata of limestone are of this kind, it being 
the common stone which is burnt for lime. The upper parts of 
these strata, he observes, are always filled with amazing quantities 
of these bodies and other marine remains, which seem to have been 
lodged there by subsidence ; and to have formed a crust over the 
limestone. This crust is generally of a very great thickness, and when 
they have passed it, they find the limestone to contain fewer marine 
remains : and at greater depths it even becomes quite pure and free 
