HOM. — HYB.] 



ECHINODERMA TA. 



255 



scutellatus, Hall, 1864, 20th Rep.N. Y. St. 



Mus. Nat. Hist., p. 357, Niagara Gr. 

 sphaericus, Winchell & Marcy, 1865, Mem. 

 Bost. Soc. Nat. Hist., vol. 1, p. Ill, Ni- 

 agara Gr. Not defined so as to be 

 recognized, 

 subglobosus n. sp. Niagara Gr. Body 

 globose ; no axial canal, hence the 

 species was sessile; seven plates in the 

 first range ; above this there are four 

 ranges below the summit of fourteen 

 plates, each with an additional plate in 

 the third range on the posterior side; 

 ambulacral orifice in the center of the 

 summit, elongated transversely, sur- 

 rounded by six plates, four of which, 

 have cicatrices for attaching spines ; anal 

 orifice near a cicatrix and near the oral 

 orifice ; the whole surface is poriferous 

 in pairs which 

 open on the sur- 

 face in orna- 

 mental sculp- 

 t u r e d figures, 

 somewhat like 

 the Greek letter 

 w, (Omega ) . 

 Collected by 

 Charles Faber, 

 in Jefferson 

 County, Indi- 

 ana, 

 subrotundus, S. A. 

 Miller, 1879, Jour. Cin. Soc. Nat. Hist., 

 vol. 2, n. 107, Niagara Gr. 

 tumidus/S. A. Miller, 1879, Jour. Cin. Soc. 

 Nat. Hist., vol. 2, p. 104, Niagara Gr. 



Fig. 338.— Holocystites 

 subglobosus. 



Fig. 339.— Holocystites turbinatus. 



turbinatus, S. A. Miller, 1880, Jour. Cin. 



Soc. Nat. Hist., vol. 2, p. 259, Niagara Gr. 

 ventricosus, S. A. Miller, 1879, Jour. Cin. 



Soc. Nat. Hist., vol. 2, p. 108, Niagar.i Gr. 

 wetherbyi, S. A. Miller, 1878, Jour. Cin. 



Soc. Nat. Hist., vol. 1, p. 131 Niagara Gr. 

 winchelli, Hall, 1864, 20th Rep. N. Y. St. 



Mus. Nat. Hist., p. 356, Niagara Gr. 

 Homocrinus, Hall, 1852, Pal. N. Y., vol. 2, 



p. 185. [Ety. homos, like ; Tcrinon, lily.] 



Basals 5 ; subradials 5 ; radials 1 x"5 ; 



azygous interradials 2; proboscis or 



ventral sac long and large ; arms bifur- 



cating; pinnules wanting; column 

 round. Distinguished from Dendro- 

 crinus by the proportionally larger 

 basals, and absence of one radial, and 

 from Poteriocrinus by the arrangement 

 of the azygous plates and absence of 

 pinnules. Type H. parvus. . ' 



angustatus, see Dendrocrinus angustatus. 



crassus, Whiteaves, 1887, Cont. to Can. 

 Pal., vol. 1, p. 95, Ham. Gr. 



cylindricus, Hall, 1852, Pal. N. Y., vol. 



2, p. 186, Niagara Gr. 



parvus, Hall, 1852, Pal. N. Y., vol. 2, p. 



185, Niagara Gr. 

 polydactylm, see Dendrocrinus polydacty- 



lus. 

 proboscidialis, Hall, 1859, Pal. N. Y., vol. 



3. p. 38, Oriskany sandstone, 

 scoparius, Hall, 



1859, Pal. 



N. Y., vol. 3, 



p. 102, Low. 



Held. Gr. 

 Hybochinus, 



Worth en & 



Miller, 1883, 



Geo. Sur. 111., 



vol. 7, p. 331. 



[Ety. hubos, 



humpbacked ; 



echinos, sea- 

 urchin.] Test 



flexible, sub- 



s p h e r o idal, 



five ambula- 

 cral areas, 



with numer- 

 ous ranges of 



i n t e rlocking 



plates imbri- 

 cating up- Fig. 340.— Homocrinus 



ward, and scoparius. 



each perforated with a pair of pores ; 



interambulacral areas narrower; plates 



imbricate downward ; surface granular ; 



jaws strong. Type H. spectabilis. 

 spectabilis, Worthen & Miller, 1883, Geo. 



Sur. 111., vol. 7, p. 332, Kaskaskia Gr. 

 Hybochinus, Billings, 1857, Rep. of Progr. 



Geo. Sur. Can,, p. 274, and Can. Org. 



Rem., Decade 4, p. 23. [Ety. hubos, 



humpbacked ; Jcrinon, lily.] Calyx pro- 

 tuberant on the 

 azygous side ; 

 basals 5 ; radials 

 1x5; azygous 

 interradials 2 ; 

 arms 5 ; no pin- 

 nules; column 

 round. Type H 

 conicus. 

 conicus, Billings, 1857, Rep. of Progr. Geo. 



Sur. Can., p. 274, and Can. Org. Rem., 



Decade 4, p. 29, Trenton Gr. 

 pristinus, Billings, 1859, Can. Org. Rem., 



Decade 4, p. 23, Chazy Gr. 

 tumidus, Billings, 1857, Rep. of Progr. 



Geo. Sur. Can., p. 275, and Can. Org. 



Rem., Decade 4, p. 28, Trenton Gr. 



Fig. 341— Hybocrinus coni- 

 cus. Diagram. 



