ECHINODERMATA. 
273 
these zoophytes exist, whilst in the early ages of the world the 
°cean must have swarmed with them. Encrmites abounded in the 
s eas during the transition and secondary epoch. It was one of the 
Iri0s t numerous of the animal tribes which inhabited the salt waters of 
“ le ancient world. In traversing some parts of France, we tread 
Under our feet myriads of these beings, whose calcareous remains form 
Vag t beds of rock. The encrinites gradually disappeared from the 
ari cient seas ; their species were diminished as the globe became older 
or modified in its conditions, so that at the present time only a few 
%pes remain in our seas — such as the Comatula of the Mediterra- 
nean ; Pentacrina, the Medusa’s-head of the Antilles ; and the Eu- 
r °pean Pentcicrinus — all of them very rare, and probably destined 
s °°n to disappear, carrying with them the last reminiscence of the 
Zoological races of the ancient world : and here lies the real interest 
U'tbch the Crino'idea presents to the thinking man. The encrmites 
*U° s t common in the fossil state are Pentacrirms fasciculosus, belonging 
the lias; Apiocrmus Boissyanus, which is found in the oolite or 
■Jurassic rocks ; and Encrinus liliformis, which appertains to the 
Classic period. These three fixed zoophytes seem to have existed 
lu great numbers during the first ages of the world— namely, the 
Silurian period. They attained their maximum of development 
during the Devonian age, when their mimbers began to decrease, 
^‘cording to M. D’Orbigny, there are thirty-nine genera found in the 
pal;,. OZ oi c rocks, two in the triassic, seven in the jurassic, five in the 
Cre taceous, and only one in the tertiary strata. Of all these genera 
°uty one, namely, Pentacrinus, is found in the modern epoch to repre- 
Sfi ut the varied forms of these the first inhabitants of the seas. 
The free Crinoidas, that is, those not rooted to the soil by a stem, 
Udiich the Comatula may be considered the type, only appeared at 
? period. They are absent in the palseozoic and triassic rocks, 
. 1 a ppear to have attained their maximum of development in the 
Jurassic period. 
The numerous fossilized remains of these curious creations, which 
a ,0l uid in different rocks, attracted the attention of learned men at an 
ea jJy period. The encrinites were among the earliest objects of 
8( Uentifi c description. As early as the sixteenth century, the celebrated 
^uieralogist, George Agricola, mentions them under the names of 
jnir ochites. Trochites, and Astroites. At the same time, and since 
