334 PROCEEDINGS OF THE 



on the other, a specimen that had been often looked at, without 

 suggesting any satisfactory purpose in use. No doubt this is a 

 detached patch similar to that above noticed. Little acquainted 

 with the observations of others, or with the special literature 

 regarding crinoids, one may possibly be dealing thus, innocently, 

 with well known facts; but what is seen among thousands of 

 fragments only once in fifty years, gives a kind of guarantee for 

 claiming such facts to be new or rare. 



3. A markedly tumid specimen, depressed and incurved on one 

 side, seemed a good example of an injured or diseased stem, 

 the depression being filled up Avith a sort of plug of mineral 

 matter. There is no decided thickening of the tumid ossicles, 

 nor any decided enlargement of surface ornamentation, but 

 staining of the stem around and under the depression is distinct. 

 The plug, doubtless, has nothing to do in the production of the 

 observed tumidity. 



4. This specimen distinctly, though slightly, tumid, with little 

 depression on one side, is also a diseased production. The slight 

 swelling seems to have been less gradual than common. Two 

 ossicles curve rather abruptly outward, including three others 

 somewhat raised and slightly thickened, but little rounded or 

 bulged. The under part of one of the union scars of a now 

 detached branch indicates that it had been connected to the 

 living animal, and so far involved in the diseased and healing 

 process, — the process of union of the branch bearing the marks 

 of altered form, or of repair, if not of symmetrical restoration. 

 It is evident that destruction and healing of parts existed j^artially 

 under the branch when attached, which is exceptional. In this 

 instance, the surface markings are enlarged near the injury, and 

 the characteristic staining of the stem also exists, with notable 

 restoration of ossicles and lines of separation. 



These instances, with those formerly given, present all the 

 features that the specimens collected and preserved afford of the 

 varieties of the "tumid," "swelled out," or "barrel-shaped" 

 crinoidea. 



In the former paper the sockets, cup-shaped cavities, or 

 variously formed fixed foot, or supporting base of the crinoidea, 

 were incidentally alluded to. A few words now may be added. 

 During long years of observation by the writer, these sockets, 

 with various other adventitious structures, were always seen to 



