VI PREFACE. 



such an undertaking, and one which, if less consistent with its beauty 

 as a work of art, might yet, it was observed, bestow an additional 

 degree of fidelity and precision on its anatomical details. 



I did follow this advice, and it is to the kind exertions of the same 

 friends that I stand chiefly indebted for the highly respectable list of 

 Subscribers who have sanctioned this work by their patronage. Great, 

 however, as is the encouragement I have derived from this circum- 

 stance, I still feel how much I must require the indulgence of the 

 Public, in venturing to appear before it as anauthor and an artist, and 

 especially on a subject so imperfectly understood as the present. 



I trust, however, that I may fairly consider myself as having 

 pointed out characters which throw a new and not unimportant light 

 on the class of beings under consideration, which mark with precision 

 the natural arrangements of their Genera and Species, and illustrate 

 many of the most essential features of their organic structure ; and 

 since the elucidations hence resulting, offer in many and material 

 instances new analogies, which may be usefully applied to the inves- 

 tigation of the other families of that important and hitherto imperfecly 

 understood natural division, the radiated Echinodermata, I am 

 willing to flatter myself that my researches may be considered as 

 adding a useful, though humble, contribution to the now rapidly 

 increasing stock of accurate Zoological knowledge. 



Since the progress of these inquiries had brought to light numerous 

 Species hitherto unknown or incorrectly ascertained, it became 

 necessary to adopt, in part at least, a new nomenclature ; from this 

 consideration, and not from any desire of capricious innovation, 

 which must, wherever it is superfluous, prove also detrimental to 

 science, 1 have suffered myself to be swayed in this subject. 



In the nomenclature I have thus proposed, I have therefore 

 retained the old and familiar derivation of the classic name from the 



