250 



ECHINODERMA TA. 



[C.RA. 



generic name, but it was not defined or 

 established; tbere are others who use 

 Gilbertaocrinus, but it, probably, is a 

 distinct genus, and, so far, not known 

 in America, 

 fiscellus, Meek & Worthen, 1861, (Trema- 

 tocrinus fiscellus,) Proc. Acad. Nat. 

 Sci. Phil., p. 383, and Geo. Sur. 111., 

 vol. 2, p. 222, Burlington Gr. 



Fio. 32t.-(jroniastero!docrlnus tuberoaus. A Is the 

 O, the opening; B, side view of vault; C, under 

 false arms; I), enlargement of base of arms. 



Fio. 322.— Three views of Uilbertsocrinus cal- 

 caratus, to show the genus Is distinct from 

 Gonlasteroidocrlnus. 



obovatus, Meek & Worthen, 1869, Proc.' 



Acad. Nat. Sci., Phil., p. 76, and Geo. 



Sur. 111., vol. 5, p. 391, Burlington Gr. 

 papillatus, Hall, 1860, (Trematocrinus 



papillatus,) Supp. to Geo. Rep. Iowa, 



p. 76, Burlington Gr. 

 reticulatus, Hall, 1861, (Trematocrinus 



reticulatus,) Desc. New Crinoidea, p. 9, 



and Bost. Jour. Nat. Hist. vol. 7, p. 325, 



Burlington Gr. 



robustus, Hall, 1860, (Trematocrinus ro- 

 bu8tus,) Supp. to Geo. Rep. Iowa, p. 

 77, Keokuk Gr. 

 spinigerus, Hall, 1862, (Trematocrinus 

 s*pinigeru8,) 15th Rep. N. Y. St. Mus. 

 Nat. Hist., p. 128, Ham. Gr. 

 tenuiradiatus. Meek & \Vurthen,1869,Proc. 

 Acad. Nat. Sci. Phil., p. 75, and Geo. 

 Sur. 111., vol. 5, p. 389, Burlington Gr. 

 tuberculosus, Hall, 1860, (Tremato- 

 crinus tuberculosus,) Supp. to 

 Geo. Rep. Iowa, p. 75, Burling- 

 ton Gr. 

 tuberosus, Lyon & Casseday, 1859, 

 Am. Jour. Sci., vol. 28, 2d ser., 

 p. 233, Kaskaskia < ; r 

 typus, Hall, 1860, (Trematocrinus 

 typus,) Supp. to Geo. Rep. Iowa, 

 p. 73, Burlington Gr. 

 Gkanatocrinus, Troost, 1850, Cat. 

 Fos8. in Am. Jour. Sci., vol. 8, 

 p. 420, and described by Hall, 

 1862, 15th Sep. N. Y. St. Mus. 

 Nat. Hist., p. 146. [Ety. gran- 

 ato8, granular ; krinon, lily.] Ca- 

 lyx subglobose oval or elliptic; 

 the proportions of the plates 

 giving a very different outline 

 to the calyx from that of a IVn- 

 ticmites; summit depressed con- 

 vex ; base flattened or concave ; 

 ambulacral areas like those in 

 Pentremites, but narrower, and 

 extending nearly or quite the 

 entire length ; basals 3, sunken 

 so as not to be visible in a 

 side view ; radials and deltoids 

 similar to those of Pentremites 

 and proportionally as variable ; 

 slender, thread-like arms, or 

 pinnules, as in Pentremites; 

 ambulacra and lancet-plates in 

 narrow sinuses; anal opening 

 as in Pentremites ; central open- 

 ing and spiracles often closed 

 by small plates; ten narrow 

 hydrospiral canals open exter- 

 nally by either five or ten aper- 

 tures. Type G. norwoodi. 

 cidariformis, Troost. Not defined, 

 cornutus, Meek & Worthen, 1861, (Pen- 

 tremites cornutus,) Proc. Acad. Nat. 

 Sci. Phil., p. 141, and Geo. Sur. 111., 

 vol. 2, p. 276, St. Louis Gr. 

 curtus, Shumard, 1855, (Pentremites cur- 

 tus,) Geo. Rep. Mo., p. 187, War- 

 saw Gr. 

 glaber, Meek & Worthen, 1869, Proc. 

 Acad. Nat. Sci. Phil., p. 91, and Geo. 

 Sur. 111., vol. 5, p. 537, St. Louis Gr. 

 granulatus, Roemer, 1852, (Pentatremat- 

 ites granulatus,) Monog. Blast., p. 43, 

 Warsaw Gr. 

 granulosus, Meek & Worthen, 1865, Proc. 

 Acad. Nat. Sci. Phil., p. 165, and Geo. 

 Sur. 111., vol. 5, p. 508, Keokuk Gr. 

 leda, Hall, 1862, (Pentremites leda,) 15th 

 Rep. N. Y. Mus. Nat. Hist., p. 149, 

 Ham. Gr. 



vault; 

 side of 



