. Geological magazine . a web-like extension of tegminal plates surfaces of E«, III on the left, bearing the median proximal anal, IV on the right,bearing the first brachial ; in each are to be seen the dorsal ligament-fossa, twomuscle-plates and fossae, and a wide ventral groove merging into a narrow tonguewhere the axial cord lay. These facts prove : (1) that r. post. Es was united to theproximal anal in the same way as to IBr^; (2) that the anal mid-rib was innervatedby the same axial cord as was the r. post. arm. From which we infer (1) that theproximal anal in locrinus actually is a plate
. Geological magazine . a web-like extension of tegminal plates surfaces of E«, III on the left, bearing the median proximal anal, IV on the right,bearing the first brachial ; in each are to be seen the dorsal ligament-fossa, twomuscle-plates and fossae, and a wide ventral groove merging into a narrow tonguewhere the axial cord lay. These facts prove : (1) that r. post. Es was united to theproximal anal in the same way as to IBr^; (2) that the anal mid-rib was innervatedby the same axial cord as was the r. post. arm. From which we infer (1) that theproximal anal in locrinus actually is a plate corresponding to an ordinary brachial in structure ; (2) that the mid-rib may have arisen as a branch of r. post, arm;(3) that, in any case, the application of the term axillare to r. post. Es in locrinus iswarranted by something more than the angularity which occurs upon the upperface, the form of the plates succeeding it to the left, and the slanting position ofthe posterior arm to the right (W. & Sp., p. 129).. 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
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