. The Devonian crinoids of the State of New York. Crinoidea, Fossil; Paleontology; Paleontology. DEVONIAN CR1NOIDS OF NEW YORK 21. food grooves over its surface. Interambulacrals in the tegmen correspond to the interbrachials (figure 14) of the cup. The mouth may be exposed or closed. In the first case it is surrounded by the five orals (figure 15); in the second case, the posterior oral may be pushed in between the four others so as to conceal the mouth. The mouth then is said to be subtegminal (figure 16). Changes from the primitive type of tegmen may take place along three different lines:
. The Devonian crinoids of the State of New York. Crinoidea, Fossil; Paleontology; Paleontology. DEVONIAN CR1NOIDS OF NEW YORK 21. food grooves over its surface. Interambulacrals in the tegmen correspond to the interbrachials (figure 14) of the cup. The mouth may be exposed or closed. In the first case it is surrounded by the five orals (figure 15); in the second case, the posterior oral may be pushed in between the four others so as to conceal the mouth. The mouth then is said to be subtegminal (figure 16). Changes from the primitive type of tegmen may take place along three different lines: (1) The ambu- Figure l6 lacrals pass over the apposed edges of the orals. Grad- ually the ambulacrals and sometimes the interambula- crals cover up the orals which, with the exception of the posterior, seem to diminish in size and sink beneath the surface. The posterior oral usually remains large, taking on the character of a madreporite, and is pushed by the increased size of the anal tube nearer the oral center. In accordance with the views of Bather (1900) the proximal (peristomial) ambulacrals become enlarged and assume A B c r 1 n u s metricus. Teg- men showing sub- tegminal mouth. 0, orals; A mb, ambula- crals. (After Wachs- muth and Springer 1888, 1897).. 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 Goldring, Winifred, 1888-1971. Albany : University of the State of New York
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpaleont, bookyear1923
