SCH. SIP.] 



ECHINODERMA TA. 



281 



tethys, Meek & Worthen, 1869, Proc. 

 Acad. Nat. Sci. Phil, p. 143, and 

 Geo. Sur. 111., vol. 5, p. 419, Burling- 

 ton Gr. 



tortuoaus, see Graphiocrinus tortuosus. 

 unicus, Hall, 1861, Desc. New Grin., p. 8, 

 and Geo. Sur. 111., vol. 5, p. 493, Keo- 

 kuk Gr. 



varsoviensis, Worthen, 1882, (Poterio- 

 crinus varsoviensis,) Bull. No. 1, 111. 

 St. Mus. Nat. Hist., p. 20, and 

 Geo. Sur. 111., vol. 7, p. 290, War- 

 saw Gr. 



venustus, Worthen, 1882, (Poteriocrinus 



venustus,) Bull. No. 1, 111. St. Mus. 



Nat. Hist., p. 24, and Geo. Sur. 111., 



vol. 7, p. 297, Kaskaskia Gr. 



wachsmuthi, see Graphiocrinus wach- 



smuthi. 



whitii, Hall, 1861, Desc. New Crin., p. 7, 

 and Jour. Bost. Soc. Nat. Hist., vol. 7, 

 p. 306, Burlington Gr. 



SCHIZOBLASTUS, Etheridge & Carpenter, 1882, 

 Ann. & Mag. Nat. Hist., vol. 9, p. 243. 

 [Ety. schiza, cleft ; blastos, bud.] Calyx 

 in form like Granatocrinus ; basals 

 confined to the base, sometimes visible, 

 in a side view ; deltoids always visible 

 in a side view ; ambulacra narrow and 

 sublinear, extending the height of the 

 calyx; lancet-plates nearly concealed 

 by the side plates ; latter from 20 to 80 

 in number ; 1 to 4 hydrospire folds on 

 each side of an ambulacrum ; spiracles 

 minute linear slits between the lan- 

 cet-plate and the deltoid ridges; sur- 

 face ornamented with striae. Type 8. 

 sayi. 



melonoides, Meek & Worthen, 1869, 

 (Granatoc.rinu melonoideas,) Proc. 

 Acad. Nat. Sci. Phil., p. 88, and 

 Geo. Sur. 111., vol. 5, p. 468, Burling- 

 ton Gr. 



sayi, Shumard, 1855, (Pentremites sayi,) 

 Geo. Rep. Mo., p. 185, Burling- 

 ton Gr. 



SCHIZOCKINUS, Hall, 1847, 

 Pal. N. Y., vol. 1, 

 p. 81. [Ety. schiza, 

 cleft ; krinon, lily.] 

 Basals 5 ; primary 

 radials 3x5; second- 

 ary radials 2 x 10; 

 interradials 5 or 

 more ; arms short, 

 branching, bearing 

 pinnules; column 

 round. Type S. no- 

 dosus. 



nodosus, Hall, 1847, Pal. 

 N. Y., vol. 1, p. 81. 

 Trenton Gr. 



striatus, Hall, 1847, Pal. N. Y., vol. 1, p. 

 316, Trenton Gr. Probably belongs to 

 another genus. 



HXKN ASTER, Meek & Worthen, 1860, Proc. 

 Acad. Nat. Sci., p. 449, and Geo. Sur. 

 111., vol. 2, p. 277. [Ety. schoinos, rope; 



Fio.427.-Schizocri- 

 nus nodosus. 



aster, star.] Pentagonal disk, with 

 angles produced into rays ; margins be- 

 tween rays concave and spinous; plates 

 alternating on dorsal side of rays, and 

 on ventral side of disk imbricating in- 

 ward and laterally toward the ambu- 

 lacra; furrows wide, deep, bordered 

 with a single row of adambulacrals, 

 which become the marginal plates of 

 the free rays. Type S. fimbriatus. 



timbriatus, Meek & Worthen, 1860, (Pal- 

 seasterina fimbriata,) Proc. Acad. Nat. 

 Sci. Phil., p. 449, and Geo. Sur. III., 

 vol. 2, p. 278, St. Louis Gr. 



wachsmuthi, Meek & Worthen, 1866, Proc. 

 Acad. Nat. Sci. Phil., p. 259, and 

 Geo. Sur. 111., vol. 3, p. 499, Burling- 

 ton Gr. 



Scyphocrinux, Hall, 1847, Pal. N. Y., vol. 1. 

 Preoccupied, by Zenker, in 1839. See 

 Cupuloctinus. 



heterocostalis, see Cupulocrinus heterocos- 



talis. 



Scytalocrinug, Wachsmuth & Springer, 1879, 

 Proc. Acad. Nat. Sci. Phil. A division 

 of Poteriocrinus of less than generic 

 importance, with P. robustus as the 

 type. 



wachsmuthi, see Poteriocrinus wach- 



nmuthi. 



SIPHONOCRINUS, S. A. Miller, 1888, Am. 

 Geol., vol. 1, p. 263. [Ety. siphon, bent 

 tube ; krinon, lily.] Basa'ls 3 (?) small. 



FIG. 428. Siphonocrinus nobilis; lateral view 

 of au internal cast. 



Wachsmuth says there are 5; pri- 

 mary radials 3x5; first interradials 

 nearly as large as primary radials, and 

 succeeded by two smaller ones, and 



