Differing essentially in their characters from every other zoo* 

 phyte, either fossil or recent, their examination, if pursued with 

 even a moderate portion of success, cannot fail to excite a high de- 

 gree of interest. It must, however, be remarked, that these circum- 

 stances, which are supposed to render the investigation so interesting, 

 are necessarily such as also tend to render it more difficult. The want 

 of analagous appearances in other substances, either recent or fossil, 

 must necessarily much impede the progress of the naturalist, who is 

 endeavouring to ascertain the original forms of these animals, by 

 putting together fragments, which have now actually become sub- 

 jects of the mineral kingdom; and which were separated and dis- 

 persed before the existence of the present world. Still greater will be 

 the difficulty, which must accompany the attempt, to obtain some cor- 

 rect notions respecting the various habitudes, and the different modes 

 of existence of these animals, from materials so imperfect. 



These bodies are separated from all the other zoophytes, by this 

 distinguishing character their trunks and limbs are formed of bones ar- 

 ticulated with each other by surfaces, marked with a Conform or stelliform 

 figure. From the external forms of these bones, a natural division 

 of these animals into two sections, or perhaps genera, takes place: 

 those, the bones of which have almost all a circular or oval circum- 

 ference, have been hitherto termed ENCRINITES ; and those, whose 

 bones nearly all possess a pentagonal circumference, have been dis- 

 tinguished by the term PENTACRINITES. 



Many of the terms which are at present applied to the respective 

 parts of these animals are undoubtedly objectionable. This is, indeed, 

 a circumstance which might with reason be expected, since these 

 names were given to the several parts soon after their first discovery; 

 before any just notion could be formed respecting their real nature, 

 or the relationship which existed between them. A fancied resem- 

 blance to some known figure was generally, therefore, the capricious 

 circumstance on which their appellation depended, as may be per- 



VOL. II. X 



