. The Cambridge natural history. Zoology. INTER-RELATIONS OF ORDERS 623 The final result, then, of all our inquiries leads us to a view of the mutual affinities of the classes of Echinoderms, which may be indicated in the following table :— Protocoelomata I First fixed ancestor Asteroidea Protopelmatozoa (Thecoidea ?) OphiuToidea Prote^hinoidea Echinoidea Holothuroidea. Crinoidea ' Blastoidea We shall hazard the prophecy that if ever pre-Cambrian Echinoderms are found, there will be amongst them small stalked forms which may be superficially classed with " Cystids," but which are in
. The Cambridge natural history. Zoology. INTER-RELATIONS OF ORDERS 623 The final result, then, of all our inquiries leads us to a view of the mutual affinities of the classes of Echinoderms, which may be indicated in the following table :— Protocoelomata I First fixed ancestor Asteroidea Protopelmatozoa (Thecoidea ?) OphiuToidea Prote^hinoidea Echinoidea Holothuroidea. Crinoidea ' Blastoidea We shall hazard the prophecy that if ever pre-Cambrian Echinoderms are found, there will be amongst them small stalked forms which may be superficially classed with " Cystids," but which are in reality the fixed ancestors of Asteroidea. They should have an irregular skeleton, and be devoid of arms, which are secondary formations; but they should indicate, by the prox- imity of the mouth to the stalk and by the relation to the stalk of the grooves for the podia, that they have diverged from the Pelmatozoan stock, and are the ancestors of Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Harmer, S. F. (Sidney Frederic), Sir, 1862- ed; Shipley, A. E. (Arthur Everett), Sir, 1861-1927. ed. [London, Macmillan and Co. , Limited; New York, The Macmillan Company
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
