REVISION OF PALEOZOIC STELLEROIDEA. 253 



t\u) namo of Sfurfzaster, with Palxocoma marstoni SaJter as tlic 

 genotype. 



In 1910 Schondorf was able to study "several rio-ht good examples" 

 of S. marstoni, and strangcdy the form turns out not to be an asterid 

 but an aulurid, with the essential ambulacral characters of Lai)- 

 worthura miltoni. He states that the ambulacrals are not alternate, 

 as stated by Salter, but opposite one another. Therefore the 

 ambulacrals and the adambulacrals are also opposite. The adam- 

 bulacrals bear two or three spmes on their outer edges, and Salter's 

 statement and figures showing two columns of ossicles outside of the 

 ambulacrals appear to be very wrong. Schondorf states that the 

 peculiar preservation of the arm skeleton has given rise to this state- 

 ment of Salter, and that there are only ambulacrals and adambula- 

 crals present. The oral skeleton is distinctly adambulacral. A 

 madreporito is not determinable. 



On the dorsal side, all that can be clearly made out is the jiresence 

 of ambulacrals and adambulacrals, all of which are arranged in trans- 

 verse rows. 



STiJRTZASTER MARSTONI (Salter). 



Palseocoma marstoni Salter, Ann. Mag. Nat. Hist., ser. 2, vol. 20, 1857, p. 328, 

 pi. 9, figs. 3a-3c. — Wright, Mon. British Foss. Echinod., Oolitic, vol. 2, 

 pt. 1 (Palaeontogr. Soc. for 1861), 1862, p. 30, fig. 17. — Qubnstedt, Petrefacten- 

 kiinde Deutschlands, vol. 4, 1876, p. 81, pi. 92, fig. 43. 



Sturtzaster marstoni Schondorf, Jahrb. nassauisch. Ver. Natiirk., Wiesbaden, 

 vol. 63, 1910, p. 217. 



Formation and locality.— CoiTim.011 in the Lower Ludlow of Church 

 Hill, Leintwardine, England. Specimens are in many museums, the 

 United States National Museum and the Yalo Museum both having 

 individuals. See S. colvini and S. cygnipes. 



Cat. Nos. 60624, 60625, U.S.N.M. 



STtJRTZASTER COLVINI (Salter). 



Palseocoma colvini Salter, Ann. Mag. Nat. Hist., ser. 2, vol. 20, 1857, p. 328. — 

 Wright, Mon. British Foss. Echinod., Oolitic, vol. 2, pt. 1 (Palseontogr. Soc. 

 for 1861), 1862, p. 30. 



Sturtzaster colvini Schondorf, Jahrb. nassauisch. Ver. Natiirk., Wiesbaden, vol. 

 63, 1910, p. 219. 



Formation and locality.— In the Lower Ludlow, Leintwardine, Eng- 

 land. ' ' Probably completely identical with S. marstoni." (Schondorf.) 



STURTZASTER CYGNIPES (Salter), 



Palxocoma cygnipes Salter, Ann. Mag. Nat. Hist., ser. 2, vol. 20, 1857, p. 329. — 

 Wright, Mon. British Foss. Echinod., Oolitic, vol. 2, pt. 1 (Palreontogr. Soc. 

 for 1861), 1862, p. 30. 



Sturtzaster cygniceps (oic) Schondorf, Jahrb. nassauisch. Ver. Naturk., ^\'ies- 

 baden, vol. 63, 1910, p. 219. 



Formation and locality. — Lower Ludlow, Leintwardine, England. 

 "Probably completely identical with S. marstoni." (Schondorf.) 



