EEVISION OF PALEOZOIC STELLEROIDEA. 237 



STtJRTZURA LEPTOSOMA (Salter). 



Protaster leptosoma Salter, Ann. Mag. Nat. Hist., ser. 2, vol. 20, 1857, p. 331, 

 pi. 9, fig. 5. — Wright, Mon. British Foss. Echinod., Oolitic, vol. 2, pt. 1 

 (Palseoutogr. Soc. for 1861), 1862, p. 33.— Quenstedt, Petrefactenkuude 

 Deiitschlands, vol. 4, 1876, p. 133, pi. 95, fig. 12.— Sturtz, Palteonto- 

 graphica, vol. 32, 1886, p. 79; N. Jahrb. fiirMin., etc., 1886, vol. 2, p. 148. 



Sturtzura leptosoma Gregory, Proc. Zool. Soc. London for 1896, 1897, p. 1035. — 

 Chapman, Proc. Roy. Soc. Victoria, n. ser., vol. 19, 1907, p. 26, pi. 8, fig. 5. — 

 ScHONDORF, Jahrb. nassaiiisch. Ver. Naturk., Wiesbaden, vol. 63, 1910, 

 p. 215. 



Rhodostoma leptosoma Sollas and Sollas, Philos. Trans. Roy. Soc. London, 

 ser. B, vol. 202, 1912, p. 223, text fig. 40, pi. 9, figs. 3, 4. 



Formaiion and locality. — Common in the Siliiric, Ludlow forma- 

 tion, at Leintwardine, Shropshire, England. 



Remarls. — Schondorf says 8. leytosoma is but a miniature edition 

 of Lapworthura miltoni, both forms being completely identical. The 

 disk margin is not convex but concave between the radii. 



STURTZURA LEPTOSOMOIDES Chapman. 



Sturtzura leptosomoides Chapman, Proc. Roy. Soc. Victoria, n. ser., vol. 19, 

 1907,p.26,pL7, figs. 1, 2;pl.8, fig.4. 



Formation and locality. — In the Siluric (Melbournian), Moonee 

 Ponds Creek, Flomington, near Melbourne, Australia. 



Genus EUGASTERELLA, new name. 



Eugaster Hall (not Eugaster Seville 1839, Orthoptcra), Twentieth Rep. N. Y. 

 State Cab. Nat. Hist., 1868, p. 290; rev. ed., 1868=1870, p. 332.— Zittel, 

 Handb. Pal., vol. 1, 1879, p. 444.— Sttjrtz, N. Jahrb. fiir. Min., etc., 1886, 

 vol. 2, p. 151.— Miller, N. Amer. Geol. Pal., 1889, p. 244.— Sturtz, Verb, 

 naturh. Ver. preuss. Rheinl., etc., vol. 50, 1893, p. 20. — Gregory, Proc. 

 Zool. Soc. London for 1896, 1897, p. 1035. 



Eugasterella Schuchert, Fossilium Catalogus, Animalia, pt. 3, April, 1914, 

 p. 19. 



Original description. — ''Body stellate, consistmg of a central alated 

 disk, and five long, slender, somewhat flexuous rays. Disk composed 

 of small, polygonal tuberculose or subspinose plates on the ventral 

 side. Rays consisting of a double series of alternating subquadrate 

 ambulacral ossicles, and a series of curved adambulacral plates 

 bordering the grooves, and forming the margin of the ray; the outer 

 ends overlap the edge of the next plate in advance. Oral plates ten, 

 arranged in pairs, forming the terminal plates of the adambulacral 

 ranges. Pores large, arranged in two rows in each ray; penetrating 

 the ray at the junction of the ambulacral and adambulacral plates 

 in such a manner that four different plates border each perforation. 

 Adambulacral and disk-plates bearing spines. Dorsal surface 

 unknown." 



Genoholotype. — E. logani (Hall). 



