672 



ECHINODERMA TA. 



[auk. i;si. 



Family Hkterocrinid.k. — Ectenocrinus, Heterocrinus, Iocrinus, Ohiocrinus. 

 Family Hybocrinid.e. — Hybocrinus. 

 Family Missourh tj n i i >.i ■:. — Missouricrinus. 



Genera Belonging to Anomalous Families. 



Family Pisocrimd.k. — Pisoeriuus. This family has five basals, followed by 

 three plates, that are both radial and subradial iu position. 



Family Edriocrimiu-:.— Edriocrinus. The base is solid in this family, and is 

 followed by five radials. 



Family Camarcm kinii> r.. — Camarocrinus. Distinct from all other families. 



Famii v A\( Yi:oi i:imi. i .— Aucyrocrinus. Distinct from all other families. 



Genera Uncertain as to Family Affinity. 



Aspidocriuus, Brach iocrinus, Coronocrinus, Cystocrious, Nipterocrinus, Pachyc- 

 rinus, and the fossil described by Hall as Myrtillocrinus americanus. 



ORDER CYSTOIDKA. 

 Family Stribalocystidk. — Stribalocystites. 



Ai'.KoTocuiM s, Miller A Gurley, 1890, Desc. 

 New Gen. and Spec Ecninodermata, 

 p. 30, and 16th Rep. Geo. 

 Sur. Ind., p. 360. [Ety. 

 (ibrotos, immortal ; Icri- 

 non, lily.] Calyx bowl- 

 shaped, depressed 

 below ; basals 5, oc- 

 cupying a shallow eon- 

 cavity; subradials 5, 

 as high as wide ; first 

 radials pentagonal, wider 

 than high, truncated 

 horizontally the entire 

 width of the plates, sut- 

 ures gaping; brachial or 

 second radials constrict- 

 ed in the middle and 

 bearing upon the upper 

 sloping sides the free 

 arms ; arms bifurcate 

 frequently and bear pin- 

 nules ; no regular inter- 

 radials. First azygous 

 plate in line with the 

 first radials, horizontally 

 truncated above and 

 having a gaping suture ; 

 second plate constricted 

 in the middle, and fol- 

 lowed by a single series 

 of plates. Type A. cy- 

 mosus, which isdescribed 

 at the same place, 

 from the Keokuk Gr. 



Actinocrinus 

 blairi and A. 

 brittsi, S. A. 

 Miller, 1892, 

 Adv. Sheets 

 18th E e p . 

 Fig. 1202.— Abrotocrinus Geo. Sur. 



oymosus. Ind., pp. 35, 



36, Burlington Gr., and A. chouteau- 

 ensis, p. 18, from the Chouteau lime- 

 Btone, and A. fossatus, p. 40, from the 

 Burlington Gr. 



Fig. 120.'!.- Actinocrinus Fig. 1204.— Actinocrinus 

 chouiiiuii'iisis. Azy- cliouteauensis. Ktim- 

 4 gous view. mit view. 



grandis, Miller & 

 Gurley, 1890, 

 Desc. New Gen. 

 and Spec. Ecni- 

 nodermata, p. 

 25, and 1 6 1 h 

 Rep. Geo. Sur. 

 Ind., p. 346, 

 Keokuk Gr. 

 nodosus, S. A. Mil- 

 ler, 1891, Bull. 

 No. 4, Geo. Sur. 

 Mo., p. 33, Bur- 

 lington Gr. 

 puteatus, Rowley & Hare, 1891, Kansas 

 City Scientist, vol. 5, p. 101, Burlington 

 Gr. 

 sedaliensis, S. A. Miller, 1892, Advance 

 Sheets 18th Rep. Geo. Sur. Ind., p. 16, 

 Burlington Gr. 

 senarius, Hall, 1860, Supp. Geo. Rep. Iowa, 

 p. 25, syn. for Physetocrinus ornatus. 

 Esiocrinus, Miller & Gurley, 1890, Jour. 

 Cin. Soc. Nat. Hist, vol. 13, p. 14. [Ety. 

 aixios, auspicious, coming at good time; 



Fig. 1205. —Actinocrinus 

 chouteauensis. Basal 

 view. 



