312 PROCEEDINOS OF THE ACADEMY OP [1881. 



Megistocr. Evansii was desnribed from the Lower, and M. plenus, and M. par- 

 virostris from the Upper Burlington limestone. The latter is evidently only 

 a young specimen of M. plenus, which cannot be distinguished sufficiently 

 from the lower bed form. It is highly probable that M. brevicomis is like- 

 wise a young stage of M. Evansii. 

 1876. Megistocr. Farnsworthi White. Proc. Acad. Nat. Sci. Phila., p. 29. Hamil- 

 ton gr., Devon. Solen and Iowa City, Iowa. 



1857. Megistocr. Knappi Lyon. Proe. Acad. Nat. Sci. Phila., p. 412, PI. 4, figs. 6 



a, b. Upper Helderberg, Louisville, Ky. 



1858. Megistocr. latus Hall. Ueol. Rep. Iowa, vol. i, pt. ii, p. 480, PI. 1, figs. 1 a, b. 



Hamiltiin gr. New Bufi'alo, Iowa. 

 1S78. Megistocr. nodosus Barris. Proc. Davenport Acad. Nat. Sci., voL ii, p. 285, 



PI. 2, fig. 4. Encrinal limest. Near Davenport, Iowa. 

 1862. Megistocr. Ontario Hall. 15th Rep. N. York St. Cab. Nat. Hist., p. 136. 



Hamilton gr. Western New York. 

 1869. Megistocr. rugosus Lyon and Cass. Amer. Journ. Sci., vol. 28, p. 243. 



Encrinal limest. Louisville, Ky. 

 1361. Megistocr. spinosulus Lyon. Proc. Acad. Nat. Sci. Phila., p. 413, PI. 4, 



fig?. 7 a, b. Upper Helderberg gr. Louisville, Ky. 

 Either this species is incorrectly figured, or it does not belong here. It slightly 



re-embles Hadrocrinus Lyon. 



e. ACTINOCRINITES. 



15. ACTINOCRINUS Miller.i 



1821. Miller. History of the Crinoidea, p. 90. 



1844. McCoy. Synop. Carb. Foss. Ireland. 



1853. De Koninck and Lehon. Rec. Crin. Belg., p. 125. 



1855. Roemer. Lethsea Geogn. (Ausg. 3), p. 246. 



1866. Meek and Worthen. Geol. Rep. 111., ii, p. 149. 



1869. Meek and Worthen. Proc. Acad. Nat. Sci. Phila., p. 153. 



1878. Meek and Worthen. Geol. Rep. 111., v, p. 340. 



1878. Wachsm. and Spr. Proc. Acad. Nat. Sci. Phila., p. 241. 



1878. Zittel. Handb. der Palaeontologie, i, p. 369, 



Not Angelin, 1878. Iconogr. Crin. Suae, p. 6. 



Under Aclinocrinus a very large number of forms have been 

 described from America and Europe, and from the Upper Silurian 

 to near the close of the Subcarboniferous, which were afterwards 

 referred to independent genera. There can be, however, no doubt 

 as to the group which should keep the name, as fortunately all of 



' In the list of references we quote only those publications which have a 

 direct or indirect bearing upon the present, greatly restricted form of the 

 genus. The following writers embraced with it, more or less, the entire 

 family : Agassiz, 1835 ; Goldfuss, 1826-1831 ; Phillips, 1886-1839; McCoy, 

 1844 ; Austin, 1842 ; D'Orbigny, 1850 ; Owen and Schumird, 1850-1852 ; 

 de Kon. and Lehon, 1853 ; Shumard, 1855 and 1866 ; Pictet, 1857 ; Joh. 

 Miiller, 1857 ; Hall, 1858, 1860 and 1861 ; McChesney, 1860 ; Schultze, 1867. 



