. Bulletins of American paleontology. Early Silurian Crinoids from New York: Eckert and Brett 23. Text-figure ?,—Tonnosocrinus furheri n. gen. and expanded plate diagram. Radials black, interbrachials stippled. D-57 uated at top of deep intracalical cylinder; diameter of infrabasal circlet slightly exceeding diameter of prox- imal column (PI. 4, fig. 7). Basal circlet comprising approximately 40% of cup height. Basals five, up- turned lower margins forming deep intracalical cylin- der. In side view, basals six-sided, wider than high (h/ w = ), lower margins concave. Radials pentag-
. Bulletins of American paleontology. Early Silurian Crinoids from New York: Eckert and Brett 23. Text-figure ?,—Tonnosocrinus furheri n. gen. and expanded plate diagram. Radials black, interbrachials stippled. D-57 uated at top of deep intracalical cylinder; diameter of infrabasal circlet slightly exceeding diameter of prox- imal column (PI. 4, fig. 7). Basal circlet comprising approximately 40% of cup height. Basals five, up- turned lower margins forming deep intracalical cylin- der. In side view, basals six-sided, wider than high (h/ w = ), lower margins concave. Radials pentag- onal, wider than high (h/w = ), separated from each other by basals, first interprimibrachials (interra- dials), and primanal. First primibrachial in each ray wider than high (h/w = ), rectangular or nearly so (upper comers slightly truncated in some instances; Text-figs. 5, 6D). Second primibrachials typically ax- illary, wider than high (h/w = ), exceptionally variable in size and shape; largest examples pentago- nal, in lateral contact with two interrays; smaller sec- ond primibrachials four-sided, in lateral contact with one interray only (Text-fig. 6A); smallest examples tri- angular with margins completely enclosed by first pri- mibrachial and first secundibrachials (Text-fig. 6D). Second primibrachial absent in C ray of BMS E26344 (PI. 4, fig. 1). Secundibrachials wider than high; prox- imal two secundibrachials in each half-ray incorporat- ed into cup. First secundibrachial five-sided, interray side bearing a fixed pinnule in all but the smallest examples of this species. Second and third secundi- brachials wedge-shaped. First and second secundibra- chials of each pair of half-rays adjoining each other laterally. All interrays similar in width, consisting of few plates. First interprimibrachial large, elongate (h/w = ), eight- to twelve-sided. Sutures between first interprimibrachial and ray series commonly strongly depressed. First interp
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