BEL.— CAC] 



ECHINODERMATA. 



229 



Belemnocrinos, White, 1862, Proc. Bost. Soc. 

 Nat.Hist., vol. 9, p. 14. 

 [Ety. belemnon, dart, 

 javelin ; krinon, lily.] 

 Basals 5, large, long, 

 narrow and of irregular 

 shape; radials5; arms 

 10, with one or two 

 syzygies in each joint ; 

 pinnules long, arm- 

 like, and bifurcating; 

 azygous plate rests be- 

 tween radials, and 

 upon one of the basals, 

 and supports a large 

 ventral sac composed 

 of numerous hexago- 

 nal plates ; column 

 pentagonal, with or 

 without lateral cirrhi. 

 Type B. typus. 



florifer, Wachsmuth & 

 Springer, 1877, Am. 

 Jour. Sci. and Arts, 

 3d ser., vol. 13, p. 256, 

 Burlington Gr. 



pourtalesi, Wachsmuth 

 & Springer, 1877, Am. 

 Jour. Sci. and Arts, 

 3d ser., vol. 13, p. 258, 

 Burlington Gr. 



typus, White, 1862, 



Proc. Bost. Soc. Nat. 



Hist., vol. 9, p. 14, 



Burlington Gr. 



whitii, Meek & Worthen, 1866, Proc. Acad. 



Nat. Sci. Phil., p. 251, and Geo. Sur. 



111., vol. 3, p. 463, Burlington Gr. 



Fig. 255— Belem- 

 nocrinus typus. 



cavity ; the deltoids occupy the whole 

 space between the pseudambulacra ; 

 the orifices unknown ; column round. 

 Type B. carcharidens. 

 carcharidens, Bill- 

 ings, 1859, Geo. 

 Sur. of Can., Dec- 

 ade 4, p. 18, Chazy 

 Gr. 



Bbachiociunus, Hall, 

 1859, Pal. N. Y., 

 vol. 3, p. 118. [Ety. 

 brachium, an arm ; 

 krinon, lily.] 



Founded upon Fig. 257.— Blastoldocri- 

 arms rounded at nns carcharidens. d, 

 ,, u deltoid plates ex- 



tne base, com- tending the whole 

 posed of single ar- length of the pseud- 

 ticulating plates ambulacra, 

 having thickened, node-like joints, and 

 bearing pinnules. Type B. nodosarius. 

 nodosarius, Hall, 1859, Pal. N. Y., vol. 3, 

 p. 118, Low. Held. Gr. 



Buhsacrinus, Meek & Worthen, 1861, Proc. 

 Acad. Nat. Sci. Phil., p. 136. [Ety. 

 buna, purse ; krinon, lily.] Calyx some- 

 what like Graphiocrinus, but arms 

 widely different ; basals 5 ; subradials 

 5 ; radials 2x5; regular interradials 0; 

 azygous interradial 1 ; arms wide, flat, 



1'ointing below, in compact series, and 

 >ifurcating above. Type B. wach- 

 smuthi. 

 confirraatus, White, 1862, Proc. Bost. Soc. 

 Nat. Hist., vol. 9, p. 11, Burlington Gr. 

 wachsmuthi, Meek & Worthen, 1861, Proc. 

 Acad. Nat. Sci. Phil., p. 137, and Geo. 

 Sur. 111., vol. 3, p. 479, Burlington Gr. 





Fig. 256.- 



-Belemnocrinus whitii. 

 Diagram x 2. 



Blastoidocrinus, Billings, 1859, Can. 

 Org. Rem., Decade 4, p. 18. [Ety. 

 blastos, a bud ; eidos, form ; krinon, 

 lily.] The general form is like a 

 Pentremites ; basals do not rest 

 upon the top of the column, but have 

 their inner edges turned upward, and 

 the column passes on into the visceral 



Fig. 258.— Bursacrinus wachsmuthi. Diagram. 



Cacabocrinus, Troost, 1850. Never de- 

 scribed. The fossils referred to it be- 

 long to Dolatocrinus. 

 16 



