xxiv 



PRELIMINARY OBSERVATIONS. 



of fossil encrinite is given, p. 164. : it is named the Lily Encrinite, be- 

 cause the arms, when folded, resemble the head of the lily. Indeed, the 

 whole class, of encrinites and pentacrinites are called crinoidea, from 

 krinon, the lily, by Mr. Millar, in his valuable work on these fossils. 

 The arms of part of a Briarean pentacrinite are represented, p. 180. 



In the encrinite, the stem is composed of numerous round plates, 

 or vertebrae ; the branches are also composed of numerous smaller, 

 but similar plates, as may be seen by referring to fig. 17. and the cuts. 

 The pentacrinite differed from the encrinite by the plates, or vertebrae, 

 of the stem and branches being pentagonal. The stems of both were 

 attached to rocks. They appear, like various polypi, to have increased 

 by throwing out lateral stems (see the above fig.). The calcareous 

 vertebrae that formed the stem and branches, were enveloped by a thin 

 coat of animal matter, which must have possessed great muscular pow- 

 er, to have enabled the animal to move its arms with great facility, 

 when seizing its prey. 



In fig. 17. the expanded arms of the upper head of the pentacrinus 

 expose the pentagonal aperture or mouth in the centre ; and a little 

 above this is a round tube or aperture, which serves for the excretion 

 of the faeces. In fig. 18., which is a head with the arms removed, it 

 will be seen, that the excreting tube projects a little above the mouth. 

 One head of the pentacrinus is represented as folded, and another as 

 partly collapsed. As these animals were enveloped in a thin fleshy 

 covering, their calcareous remains may be regarded as portions of the 

 skeleton. Some beds of mountain limestone, in Derbyshire, are al- 

 most entirely composed of broken stems and branches of encrinites, 

 not uncommonly called entrochites. In a part of this work it was 

 stated, on the authority of a letter sent to the Author, that the Lily 

 Encrinite had been discovered in Ireland ; but the cut subsequently 

 given of it in Mr. Loudon's Magazine of Natural History^ makes 

 it doubtful, whether it is the true Lily Encrinite, or a species nearly 

 resembling it. 



The Author cannot conclude these remarks, without expressing a 

 wish, that scientific voyagers and medical gentlemen, who visit trop- 

 ical seas, would carefully examine the diflferent species of sepia that 

 may be caught. It is probable, that there are living species, with in- 

 ternal chambered shells, resembling more or less the figures in plate 

 VIII. Cuvier says, that a little change in the structure of the oval 

 internal shell of the cuttle fish, would convert it into the internal 

 chambered shell of the spirula. It was with a view to excite the curi- 

 osity of voyagers, when near the coast of North America, that the 

 Author has suggested the possibility of the ichthyosaurus visiting those 

 seas, p. 213. Cuvier too hastily conjectured that no new living spe- 

 cies of large terrestrial quadrupeds remained to be discovered. The 

 gigantic tapir and new species of elephants have since been discovered 

 in India. The Author considers it far from improbable, that the great 

 mastodon may exist in some of the unexplored recesses on the west- 

 ern side of North America ; and he would particularly recommend 

 comparative anatomists to examine the structure of the Grisly bear, 

 and compare it with the skeleton of the cavern bear, (ursus spelaeus.) 

 When Cuvier published the last edition of his Regne Animal, in 

 1829, he does not appear to have known any thing respecting the 

 Grisly bear. 



