62 CALAMOCEINUS DIOMED.E. 



The stem of Zeacrinus coxaiius has a very similar structure (Plate XXVIII. 

 Fig. 1). 



The stem of Dorjcrinus mississippiensis, Roenier, figured by Wachsmutli 

 and Springer (Geol. Survey of 111., Vol. VIII. Plate XII. Fig. 4), has about 

 fourteen or fifteen uniform joints followed by joints projecting beyond 

 the outline of the column, separated by flat thin joints which gradually 

 increase from one or two between successive joints to six or seven. 



Poteriocrinus (Plate XII. Fig. 2) has a very wide stem at the top, 

 gradually becoming smaller, and the joints placed closer together. 



Batocrinus (Plate XV. Fig. 4) has a stem with large joints, gradually 

 passing to a closely packed column; at the top there appear to be some 

 new joints. 



Figures of Taxocrinus Fletcheri, Worthen (Plate XV. Figs. 6, 9), show 

 stems tapering very gradually from the top, made up of closely packed 

 flat joints, gradually increasing in height, and passing into larger joints 

 projecting beyond the outline, and separated by one flat joint of less 

 height and of a less diameter. 



In Toxocrinus polydactylus, figured by McCoy (Cai-bonif. Fossils of Ire- 

 land, Plate XXVI.), the upper part of the stem is composed of about twenty 

 thin joints of greater diameter than those below it. (The upjDer jjart of 

 the column is suddenly dilated.) 



Wachsmuth and Springer figure (Geol. Survey of 111., Plate XV. Vol. 

 VIII.) tapering stems of Batocrinus and of Platycrinus. They also figure 

 on the same plate the upper part of the stem of Taxocrinu.s, showing the 

 upper joints of the stem to be closely packed, and flat compared with 

 those of the lower part of the stem. 



Tapering joints do not necessarily mean a free existence, as Carpenter 

 has noticed when speaking of Eucalyptocrinus, Hall,* which has a spreading 

 root. 



Pentacrinus decorus has when young a well marked tapering stem. See 

 Chall. Eep., Plate XXXV. Fig. 1, showing a young stem of 60 mm. 



Miller f has figui'ed Dendrocrinus and Glyptocrinu,s, which evidently were 

 free ; the column of the former long and tapering, that of the latter 

 often found wound round other objects by means of an extremely flexible 

 column. 



* Twenty-eighth Ann. Rep. New York State Mus. of Nat. Hi.st., 1879, Plate XVII. Fig. 5. 

 t A. S. Miller, Cincinnati Jotirn. of Nat. Hist., Vol. 111. p. 23.3, Plate VII., 1880. 



