1881.] NATURAL SCIENCES OP PHILADELPHIA. 317 



1858. Actinocr. coelatus Hall (Sect. B). Geo). Rep Iowa, i, pt. ii, p. 585, PI. 10, 

 figs. 14, a, b; Meek and Worthen, Geol. Rep. Illinois, v, p. 341. Lower 

 Burlington limest. Burlington, Iowa. 

 1844. Actinocr. constrictus McCoy (Sect. A). Synop. Carb. Foss. Ireland, p. 181, 



PI. 27, fig. 3. Mount, limest. Ireland. 

 1844. Actinocr. costus McCoy. Synop. Carb. Foss. Ireland, p. 181, PI. 26, fig. 2 ; 

 de Kon. and Lehon, 1853, Recher. Crin. Belg., p. 129, PI. 3, figs. 2, a, b and 

 PI. 4, figs. a-d. Mount, limest. Ireland, and Tournay, Belg. 

 It seems very probable that A. costus, A. Iffivis and A. tennuis are synonyms, 

 1864. Actinocr. Baphne Hall (Sect. B). 17th Rep. N. York St. Cab. Nat. Hist., p. 

 52: also 1873, Geol. Rep. Ohio Paleont., ii, p. 162, PI. 11, fig. 11. Waverly 

 sandstone. Richfield, Ohio. 

 1843. Actinocr. decadactylus Portlock (not Goldf. = Melocr. decadactylus). Geol. 



Rep. Londonderry, p. 349. Mount, limest. Ireland. 

 1853. Actinocr. deornatus de Kon. and Lehon. Recher. Crin. Belg., p. 142, PI. 3, 

 figs. 5, a, b. Mount, limest. Tournay, Belg., and Wexford, Engl. 

 Probably A, df ornatus, A. stellatus, A. dorsatus, and perhaps A. icosidac- 

 tylliB arc synonyms. 

 1853. Actinocr. dorsatus de Kon. and Lehfn. Recher. Crin. Belg., p. 139, PI. 4, 

 figs. 5 a, b; Meek and Worthen (Sect. A), Geol. Rep. 111., ii, p. 149. Mount, 

 limest. Tournay, Belgium. 

 «1869. Actinocr. ectypus Meek and Worthen. (Strotocr. ectypus). Proe. Acad. Nat. 

 Sci. Phila., p.' 159; also 1873, Geol. Rep. 111., v, p. 253, PI. 7, fig. 5. Lo«er 

 Burlington limest. Burlington, Iowa. 

 This is a good Actinocrinas, the type specimen was depressed, and thereby 

 had obtained an unnatural expression somewhat like Strotoorinus 

 1861. Actinocr. exoerptus Hall (Sect. B). Desc. New Sp. Crin., p. 3; also, Bost. 

 Jour. Nat. Hist., p. 276; Meek and Worthen, Geol. Rep. 111., v, p. 341. 

 Lower Burlington limest. Burlington, Iowa. 

 A very doubtful species, probably S'l/n. of A. proboscidialis. 

 1860. Actinocr. Fosteri McCbesney (Sect. B). Desc. New Pal. Foss., p. 19 ; also, 

 1867, Chicago Acad. Sci., p. 14, PI. 5, fig. 2; Meek and Worthen, Geol. Rep. 

 111., V, p. 341. Lower Burlington limest. Burlington, Iowa. 

 1860. Actinocr. glans Hall. Supp. Geol. Rep. Iowa, p. 16. Upper Burlington 

 limest. Burlington, Iowa. 

 Syit. Actinocr. tholus Hall, 1860. Supp. Geol. Rep. Iowa, p. 35. 

 Syit. Actinocr. eryx Hall, 1861. Desc. New Pal. Crin., p. 12. 

 This is a very variable species. The plates of the body ic the lower layers at 

 Burlington are scarcely convex, higher up, almost tuberculous, specimens of 

 the former kind being described as A. glans, those of the latter as A. tholus. 

 As A. eryx Halt redescribed a species of A. glans in which arms and anal 

 tube were preserved, and in his photographic plates, which were distributed 

 several years later. Hall unfortunately confounded his A. eryx (we examined 

 the type specimen now in the Museum of Comparative Zoology at Cambridge), 

 with Megistoor. Whitei, which has branching in place of simple arms, and 

 no anal tube. 

 The species deviates somewhat in its general habitus from Actinocrinus, and 

 we therefore place it here with gome doubt. 

 1S60. Actinocr. Hurdianus McChesney (Sect. B). Desc. New Pal. Foss., p. 24; 

 also 1867, Chicago Acad. Sci., p. 17, PI. 5, figs. 24: Meek and Worthen, 

 Geol. Rep. 111., v, p. 341. Lower Burlington limest. Burlington, Iowa, 



