Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/328

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324
PHYSIOLOGICAL CONSIDERATIONS.

the degree, to which the individuals of these species multiplied among the first inhabitants of the sea, from the countless myriads of their petrified remains which fill so many Limestone beds of the Transition Formations, and compose vast strata of Entrochal marble, extending over large tracts of country in Northern Europe and North America. The substance of this marble is often almost as entirely made up of the petrified bones of Encrinites, as a corn-rick is composed of straws. Man applies it to construct his palace and adorn his sepulchre, but there are few who know, and fewer still who duly appreciate the surprising fact, that much of this marble is composed of the skeletons of millions of organized beings, once endowed with life, and susceptible of enjoyment, which after performing the part that was for a while assigned to them in living nature, have contributed their remains towards the composition of the mountain masses of the Earth.[1]

Of more than thirty species of Crinoïdeans that prevailed to such enormous extent in the Transition period, nearly all became extinct before the deposition of the Lias, and only one presents the angular column of the Pentacrinite; with this one exception, pent angular columns first began to abound among the Crinoïdeans at the commencement of the Lias, and have from thence extended onwards into our present seas. Their several species and even genera are also limited in their extent; e. g. the great Lily Encrinite (E. moniliformis) is peculiar to the Muschelkalk, and the Pear Encrinite to the middle region of the Oolitic formation.

The Physiological history of the family of Encrinites is very important; their species were numerous among the most ancient orders of created beings, and in this early state their construction exhibits at least an equal if not a higher

  1. Fragments of Encrinites are also dispersed irregularly throughout all the depositions of this period, intermixed with the remains of other contemporary marine animals.