150 BULLETIN 88, UNITED STATES NATIONAL MUSEUM. 



Genus PALASTERINA McCoy. 



Palasterina McCoy, British Pal. Foss., 1851, p. 59 (not defined). — Salter, Ann. 

 Mag. Nat. Hist., ser. 2, vol. 20, 1857, pp. 324, 327.— Billings (part), Geol. 

 Surv. Canada, Can. Org. Rem., dec. 3, 1858, p. 76. — Zittel, Handb. Pal., 

 vol. 1, 1879, p. 453.— Sturtz (part), Palseontographica, vol. 36, 1890, p. 226; 

 (part). Verb, naturh. Ver. preuss. Rheinl., etc., vol. 50, 1893, pp. 43, 60. — 

 ScHONDORr, Jahrb. nassauiscb. Ver. Naturk., Wiesbaden, vol. 63, 1910, 

 p. 220. 

 Palxasterina Gregory, Geol. Mag., dec. 4, vol. 6, 1899, p. 349 (complete 

 synonymy bere). 



The term Palasterina was used by McCoy in the following words: 

 ''Before I was aware Prof. Forbes had described them [the three 

 species named below] it seemed to me that the U [rasterella] ruthveni 

 and U. Jiirudo, as well as the similar American species, might be easily 

 separated from the great starfishes forming the recent genus Uraster, 

 by their small size and much more simple skeletons, and I had named 

 the genus Urasterella in my manuscript. The U. primsevus I thought 

 generically distinct from the other two, as the rays were not contracted 

 at base, etc.; and I had named it Palasterina, from its resemblance 

 to the recent genus Asterina." 



The three species mentioned by McCoy had been described by him 

 in manuscript, but on learning that descriptions had been previously 

 pubhshed by Forbes, the former, in his "British Palaeozoic Fossils," 

 adopted the names of Salter. In writing of these three forms, as 

 above quoted, he uses the generic name Palasterina (not Palxasterina, 

 the generally accepted form), and while a type-species is selected, yet 

 McCoy did not point out a single generic character of present value. 

 His statement that "the rays were not contracted at base" is a 

 feature which at that time distinguished Palasterina from Urasterella, 

 but now many Paleozoic genera are known having rays "not con- 

 tracted at base." 



While McCoy does not strictly propose the generic name, Salter is 

 the first to accept and de^e Palasterina, which he does in the following 

 words : 



"Pentagonal, depressed, the arms a little produced, with three or 

 five principal rows of tubercles above, combined with a plated disk 

 which fills up the angles; ambulacra rather shallow, of subquadrate 

 or sHghtly transverse ossicles, bordered by a single row of squarish 

 large plates, the lowest of which (ad-oral adambulacral plates, Huxley; 

 angle-ossicula, Forbes) are large and triangular, bearing combs of 

 spines (Upper Silurian)." 



Recently Gregory, in a paper entitled "On Lindstromaster and the 

 classification of the Palseasterids •" (1899), redefines the genus, basing 

 his definition largely on P. honneyi. In this connection he writes : 



"The species [P. bonneyi] is of interest, as the structure is better 

 preserved than in the type of the genus [P. primseva], and thus we are 



