302 PROCEEDINGS OF THE ACADEMY OF [1879. 



1861 Homocr. proboscidialis Hall. Geol. Rep. N. Y., vol. iii. p. 38, pi. 82, figs. 



24, 25. Oriskany sandstone. Cumberland, Md. 

 1861. Homocr. scoparius Hall. (Type of the genus ) Geol. Rep. N. Y., vol. iii. 



p. 102, pi. i. figs. 1-9. Lower Helderberg. Litchfield, N. Y. 



6. CYATHOCRINUS Miller. 

 (Diagram PI. 1G, Fig. 8.) 



1821. Miller. A History of the Crinoidea, p. 85. 



1834. Agassiz. Mem. de la Soc. de Neuch., vol. i. 



1843. Austin. Monogr. Rec. and Foss. Crin., p. 59. 



1853. De Koninck and Lehon. Rech. s. les Crin. Carb. Belgique, p. 81. 



1858. Hall. Geol. Surv. Iowa, vol. i. pt. ii. p. 622. 



I860. Meek and Worthen. Geol. Rep. 111., vol. ii. p. 175. 



1873. Meek and Worthen. Geol. Rep. 111., vol. v. p. 400. 



1877. Wachsmnth. Am. Journ. Sci. (August No.), p. 120. 



1878. Wachsm. and Springer. Proc. Acad. Nat. Sci. Phila., p. 256. 



Syn. 1859. PalcBocrinus Billings. Geol. Rep. Can., Decade IV. p. 24. 

 Syn. SpJuerocrinus Roemer. 1851. Beitrage, z. foss. fauna a. 

 Rhein, p. 13. 



In the Thesaurus Devonico-Carboniferus, Dr. Bigsby calls Cya- 

 thocrinus very appropriately " a genus full of errors." This un- 

 fortunate condition is largely clue to the confusion existing among 

 Miller's typical species, which embrace an assemblage of very dis- 

 tinct types. It seems even doubtful whether an} 7 of his species 

 can be properly ranked within the genus, and this would naturally 

 suggest the question whether Cyathocrinus, as Roemer lias sug- 

 gested, ought not to be given up altogether. We are of opinion, 

 however, that the genus ought to stand, and that it can be so 

 amended as to include certain forms of Crinoids which have been 

 referred to it by later palaeontologists, and which cannot be in- 

 cluded in any other established genus. 



Miller describes the genus substantially as follows: "Column 

 round or pentangular; calyx composed of a saucer-shaped pelvis 

 consisting of five plates, on which are in successive series five costal 

 plates, five scapulse, and one intervening plate, with an arm pro- 

 ceeding from each scapula having two hands and several fingers." 

 A comparison will show that this description differs from Pote- 

 riocrinus in but a single point, viz., Cyathocrinus has but one 

 intervening or anal plate, Poteriocrinus two or more. 



Miller refers to Cyathocrinus the following four species : 1. C. 

 planus, which ought to be the type of the genus. 2. C. tubercu- 

 latus, which has since been referred to Taxocrinus. 3. C. rugosus 



