THE CRINOIDEA 



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'O 



FIG. XCIII. 



plates in dorsal cup ; with diehotomous arms relatively slightly developed. 

 Genera Codiacrinus, Schultze (1867 ; Follmann, 1887), Devonian, Ger- 

 many (Fig. XCIIL). Lecythiocrinus, White, 

 (1880), Coal Measures of Illinois and Kansas. 

 Both genera little known ; Codiacrinus is 

 compared by Schultze with Myrtillocrinus, 

 by W. & Sp. with Achradocrinus. FAMILY 9. 

 CUPKESSOCRINIDAE. Cyathocrinoidea with 

 no anal plates in dorsal cup ; anus piercing 

 tegmen ; arms unbranched (or [?] forking few 

 times) ; stem square in section, with an axial and 4 peripheral canals (cf. 

 Lecythocrinus, p. 175). Genera Cupressocrinus, Goldfuss (1826 ; synn. 

 Halocrinus & Cypellocrinus of Steininger ; see W. & Sp., 1886, and 

 Neumayr, 1889), Devonian, Germany and England (Fig. XCIV.). A 

 massive form with basin-shaped cup ; IBB fused (by some held to be a 

 proximale, Fig. XCIV. 3) ; a stout arm, composed of a few large Br in 

 single series, rests on a facet the full width of each R ; large ambulacrals 

 cover the arm-grooves and are taken for pinnules by Zittel ; the solidity of 

 the close-fitting arms renders a plated tegmen unnecessary, but the 5 orals 



Analysis of cup of Codiacrinits 

 Schultzei. * shows position of anus. 



FIG. XCIV. 



Cupressocrinus (after L. 

 Schultze). All two -thirds nat. 

 size. 1, C. inflatus, complete 

 crown. 2, C. abbrcviatus, ventral 

 surface of calyx, slightly modi- 

 fied ; shows " consolidating ap- 

 paratus" of live plates (A), here 

 regarded as orals, between which 

 are the passages (v.g) for organs 

 of the ventral groove other than 

 the food-groove ; a.c, axial canal 

 of radial ; As, passage for rectum. 

 3, infrabasal circlet of same, from 

 below, showing sutural surfaces 

 (s) for basals, axial canal, and 

 peripheral canals (p.c). 



characteristic of Cyathocrinoidea are retained as a frame (" consolidating 

 apparatus" of authors) around the ventral surface of the cup, post. 

 being larger than the others and pierced for the rectum (Fig. XCIV. 2). 

 Myrtillocrinus, Sandberger (1855, syn. Ancyrocrinus, Hall, see p. 134, 

 Fig. LI.), Devonian, Germany, and N. America ; may have closer affinities 

 with Gasterocomidae. FAMILY 10. GASTEROCOMIDAE. Cyathocrinoidea with 

 anus in side of cup, at a level varying with the genus, either above or 

 below a;, which is always within limits of cup. Arms apparently small, 

 borne on a narrow horseshoe-shaped facet, with distinct axial canal. O 

 for most part covered by Amb, post. a large madreporite. IBB small, 

 often fused into 3 plates or 1. Stem usually of Cupressocrinid type. 

 Genera Gasterocoma, Goldfuss (1839, W. & Sp., 1886 ; Jaekel, 1895 ; 

 synn. Epactocrinus and Ceramocrinus, J. Miiller, 1855), Devonian, Ger- 

 many ; anus below x t which is in line with RR ; IBB fused into one. 

 Nanocrinus, J. Miiller (1856, Schultze, 1867), Devonian, Eifel ; like 



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