48 Slonc Lilies of the Trenton Limestone, 



ARTICLE V. — On the Crinoidea or Stone Lilies of the Trenton Limestone, 

 with a description of a new species. 



"We pass now to the examination of a very beautiful class of fossil ani- 

 mals, of which the Canadian rocks have furnished some of the most magnifi- 

 cent and interesting specimens yet discovered. The European species have 

 been long known under the various titles of Stone Lilies, Encrinites. or Cri- 

 noidea, and although their remains in a very fragmentary state, are per- 

 haps the most abundant of all fossils, yet specimens approaching to perfection 

 are comparatively rare. Few collectors have had the good fortune to dis- 

 cover half-a-dozen of those highly prized pala^ontological jewels. 



In the Trenton Limestone in the neighbourhood of the City of Ottawa, 

 a large number, nearly three hundred — many of them with all their parts, 

 even to the delicate hair-like tentacula which fringed their branching arms, 

 have been collected in a very good state of preservation within the last few 

 years. They constitute between thirty-five and forty new species, and more 

 than one half of them are of genera, hitherto unknown. 



This is a very large number to be found in any one formation, and it 

 would thus appear that that portion of the Silurian ocean which covered 

 Canada during the epoch of the Trenton Limestone, was particularly well 

 adapted to the nature of those animals and also to the preservation of their 

 remains. There is plenty of evidence to show that as many as twenty species, 

 some of them of a widely different structure from others, were all living 

 together within an area of two hundred vards in diameter at the same time. 

 That number of species has been collected from the surface of a single bed 

 of the limestone which can be traced uninteruptedly for a greater distance 

 alono- the clifts upon the shores of the Ottawa. Li the midst of these, or 

 scattered about in little groups, among them, were also eight or ten species 

 of Cystideaus — animals closely allied to the crinoids in their structure, but 

 mounted upon a much shorter stem. The long stalks of the crinoids raised 

 their heads generally from two to four feet above the bottom, while none of 

 the cystideans attained a greater height than from three to six inches. The 

 two tribes appear not to have been enemies of each other, because they 

 srrew tosrether in submarine fields of considerable extent ; the encrinites 

 towering above and overshadowng, as it were, their more humble companions. 



As we shall have occasion in this journal to describe some of these 

 fossils, it seems proper in this place to give a general outline of their 

 structure. 



The Crinoidea were, at least the gTcater numlier of them, of an 

 oval shape, and covered by an armour of small flat plates, which were 

 always of an angular form, and accurately fitted together, so as to enclose 

 the animal completely, like an egg in its shell. Attached to one end was a 

 long flexible stalk, and in or near the centre of the other extremity, a small 

 aperture which served the purpose of a mouth. Around the mouth there 

 were arranged in a circle a number of arms more or less branched in the 



