of the coal beds have been known to occur. Like 

 their stalked cousin, the crinoid, these free forms 

 appear to have been furnished with cilia for the 

 wafting of food to their mouths. 



From this latter fact alone, the inference is 

 inevitable that all echinoderm forms prior to their 

 appearance as indicated by their fossils, were 

 fixed; that is to say, they were stationary animals 

 having no locomotor appendages whatever. How- 

 ever, it is from another kind of evidence that I 

 shall attempt presently to prove, as fully as such 

 a thing can be proved, that this was actually the 

 case. 



In speculating further on their early history, the 

 question next arises as to what was the primitive 

 form, what was the appearance of the first echin- 

 oderm, what were the salient features of that most 

 ancestral creature whose descendants diverged to 

 form the five classes into which the group is now 

 divided. 



As idle as this speculation may appear, it is, 

 nevertheless, possible to find a few helpful frag- 

 ments of information among those foundation 

 stones of natural science known as embryology and 

 morphology; and with these pieces, a passable 



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