. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 402 Prof. Beyrich on the Base {Pelvis) The base in both genera is exceptionally small, and for the most part covered by the stem; its composition was unknown to or misunderstood by the founders of the genera. That Taxocrimis possesses a dicyclic tripartite base was first esta- blished by Johannes Mliller; in Forbesiocrinus it was first observed by Hall in species from the Carboniferous Limestone of America. Among the materials in the Berlin Museum, the composition of the base
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 402 Prof. Beyrich on the Base {Pelvis) The base in both genera is exceptionally small, and for the most part covered by the stem; its composition was unknown to or misunderstood by the founders of the genera. That Taxocrimis possesses a dicyclic tripartite base was first esta- blished by Johannes Mliller; in Forbesiocrinus it was first observed by Hall in species from the Carboniferous Limestone of America. Among the materials in the Berlin Museum, the composition of the base was visible in a well-preserved Taxo- crimis tuberculatiis, and in two isolated calycine bases from the Carboniferous Limestone of Bollandand of Altwasser,in Silesia, of which the first probably belongs to Forbes iocrinus nohilis^ and the other to a still unknown species of the same genus. In the two calycine bases the inner basal circle is very small, and visible with distinctly preserved sutures only on the inside of the base ; on the outside, in the surface of attachment of the stem, no sutures presented themselves, even on the applica- tion of acids ; so that in perfectly preserved heads the com- position of the base in these species would hardly be demon- strable. In the three observed cases the sutures of the inner basal circle exhibited the position shown in the annexed figure. As the segments of the second basal cir- cle alternate with those of the first, the pentagon, compared with that of the monocyclic base of PlatycrinuSj has received a re- versed position, and the sides now correspond with the interradial, the angles with the radial, direc- tions of the calyx. The segments and the sutures of the symmetri- cally divided lower basal circle Taj-ocn'nu'^. have acquired a totally difterent position; but the direction of the dorsal axis has remained precisely the same; as in Platj/crinus, it passes from the right adjacent radius to the left abjacent interradius. In order
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