PLATE II. 



Isocrinus knighti Springer (p. 25). 



U. S. Nat. Mus. Springer A-H, type. (After Springer.) 



Figure 1. Large specimen A; with bifurcating arms complete and part of stem; cirri mostly lost. 

 la. Syzygy at IIIBr 79+80 of same specimen. 



2. Large specimen, B, with stem 140 millimeters, and part of arms. Some arms of another individual 



attached. 

 2a. Detail of stem at "a" of same specimen, showing interarticular pores, X 2. 

 2b. Detail of same at "b", showing cirrus sockets, X 2. 



3. Small specimen, C, with part of arms, some not bifurcating. 



3a. Calyx and lower IIIBr of same specimen, showing form and proportions of basal and radial plates, X 2. 



4. Small specimen, D, with part of arms, one with an axillary, and some apparently simple. 



5. Small specimen, E, with two arms simple and one bifurcating at 23d IIIBr, stem detached, exposing 



infrabasals. 

 5a. Basal view of same specimen, showing infrabasals, X 4. 

 6-8. Portions of different stems, F, G, H, showing cirri. 



7a. The longest cirrus on specimen G, X 2. 

 9-13. Weathered stem joints associated with the other specimens: 9, 10, 11 are mature internodals; 12 is the 

 proximal face of a nodal incised by the cirrus sockets; 13 is a deeply stellate joint from the youngest part 

 of the stem; all X 2. 



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