| OCR Text |
Show 1895.] MR. F. A. BATHER ON UINTACRINUS. 985 accuracy of the figures. Were it not for the fact that Mr. Hill's diagram has already woefully failed us, one would not doubt it any more than Clark's ; but till M r . Hill has explained how the various plates of his analysis can be fitted together, his drawing must inevitably be neglected. Despite the considerable variation among the interbrachials, there is no evidence to show that in a single individual any one of the interradii was so different from the others as to suggest its being an anal interraclius. The interdistichals have been described by all previous writers as two in number. Certainly this number preponderates ; but 20 specimens in the British Museum, of which 28 interdistichal areas can be examined, show 2 interdistichals in 10 areas, e. g. b, f (figs. 6, 8), 3 in 6 areas, e. g. p (fig. 7), 4 in 6 areas, e. g. y, I (fig. 4), 4 or 5 in 1 area, 5 in 4 areas, e. g. d, k, g (figs. 10, 11), and 8 in Fig. 10. Uintacrinus socialis, part of Brit. Mus. E6527, d, showing fixed distichals and pinnules, interbrachials, interdistichals, and interpinnulars. Natural size. Fig. 11. Fig. 12. Uintacrinus socialis, interdistichal areas of Brit. Mus. E 6527, h (fig. 11), and E 6528, a, (fig. 12). Natural size. 1 area, viz. in a (fig. 12). The interdistichals are surrounded by HBri 2 3,4 a n d by o n e or ^wo ossicles of the proximal radiad pinnules. The proximal interdistichal is usually heptagonal, and abuts on IIBri, 2, &3 and on the succeeding interdistichal. It may, however, not reach so high as IIBr3, and it may not sink |
