. Geological magazine . Fig. 18.—Ossicles of locrimis, probably I. suhcrassus, in Mus. Comp. Zool. Eight posterior inferradial (Ei) and superradial (Es) and first primibrach(IBri) seen from interior of cup. II. Upper articular surface of Ei; groove onleft goes to X, that on right to brachials. III. Left upper articular surface ofEs, sup])ortiug x. IV. Eight upper articular surface of Es, supporting iBr^.(Enlarged.) Beviews—Wachsmuth Sf Springers Monograph on Crinoids. 43 between them. In Uintacrinus some pinnules (which are onlylesser arm-branches) are so modified by this incorporat
. Geological magazine . Fig. 18.—Ossicles of locrimis, probably I. suhcrassus, in Mus. Comp. Zool. Eight posterior inferradial (Ei) and superradial (Es) and first primibrach(IBri) seen from interior of cup. II. Upper articular surface of Ei; groove onleft goes to X, that on right to brachials. III. Left upper articular surface ofEs, sup])ortiug x. IV. Eight upper articular surface of Es, supporting iBr^.(Enlarged.) Beviews—Wachsmuth Sf Springers Monograph on Crinoids. 43 between them. In Uintacrinus some pinnules (which are onlylesser arm-branches) are so modified by this incorporation that theyhave lost their original brachial character almost to their belongs to a family in which there is as a rnle noanal tube of any consequence; but in this genus the tube is20 mm. long and 5 mm. in diameter half-way up, and, accordingto Alexander Agassiz, it was for more than half its length rigiillysoldered to the edge of the adjacent arm and pinnule joints. ^ The. Fig. 19.—Calamoerimis Biomedece. I. Posterior view of cup, showing attachment of anal tube to pinnules and proximal ( x f , from pi. iii, fig. 3.) II. Eadial and proximal brachials seen from inside of cup, showing attachment of interbrachials. (Much enlarged, and combined from pi. iii, fig. 6, and pi. xx,fig. 2.) III. A similar portion seen from the side, showing the interbrachials (unshaded) attached to the brachials and pinnulars (shaded). (Enlarged, from pi. iii, fig. 5.)All after AI. Agassiz. As, anus; B, basal; IBr, primibrachs; iBr, inter-brachials ; pn, pinnulars. food-grooves of the pinnules involved enter the tegmen at somedistance from the bases of the pinnules, and thence pass to themouth. Thus half the pinnule supports a food-groove withassociated organs, while the other half supports an anal tube(Fig. 19). We have only to suppose the attachment of the tubeto the first pinnule of the right posterior arm for a greater distance,and we should see a state of thin
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