REVISION OF PALEOZOIC STELLEEOIDEA. 125 



the arrangement of the interbrachial plates made irregular. In a 

 specimen from Jefferson County, Indiana, there are 3 pairs of inter- 

 brachial marginals instead of 2 as in the Ohio individuals. There- 

 fore there are also more adambulacrals here, 14 pairs against 10 in 

 the typical specimens. 



Formation and locality. Two free specimens of this magnificent 

 starfish were found in the Richmond formation near Waynesville, 

 Ohio. Originally pieces of these two individuals were glued together 

 as one specimen, which is the cause of our figures being less perfect 

 than Mr. Miller's. Fragments of seven other individuals were found 

 in the vicinity of Waynesville. In the University of Chicago col- 

 lection (No. 10981) there is a specimen from Jefferson County, 

 Indiana, apparently of this species. Mr. Vaupel secured the distal 

 portion of a ray of an apparently young example of this species in 

 the Maysville beds on Rons Hill, Cincinnati, Ohio, and Mr. Ulrich 

 has fragments of four individuals from the Maysville strata about 

 Cincinnati, and Covington, Kentucky. 



Remarks. This species is readily separated from the other species 

 of Promopalxaster by the marked diagonal rows of abactinal plates. 

 Actinally P. magnificus is readily distinguished from P. exculptus and 

 P. spinosus in having five instead of three interbrachial marginal 

 plates in each area, in the rapidly increasing size of the plates in the 

 inframarginal and adambulacral columns, and in the proximal am- 

 bulacral plates. P. speciosus differs at once from P. magnificus in that 

 its abactinal plates are arranged in regular longitudinal columns, 

 are far less numerous, larger and are all nearly of a size. 



This is one of the largest and best preserved of American Paleozoic 

 starfishes. P. dyeri may be a larger species but is distinguished abac- 

 tinally not only by the arrangement and difference in the forms of 

 the plates but also by the short, thick, blunt spines which now ap- 

 pear to have no definite arrangement, while P. magnificus has all of 

 its very fine spines arranged in diagonal rows like the plates. 



Cat. Nos. 40883, 60621, 60622, U.S.N.M. 



new subfamily. 



Aberrant Promopalaeasteridae with the axillary and interbrachial 

 areas composed entirely of adambulacral pieces. 

 Contains : 

 Anorihaster. 



ANORTHASTER, new genus. 



Plate 13, fig. 4; plate 20, fig. 1. 

 Anorthaster SCHUCHERT, Fossilium Catalogus, Animalia, pt. 3, April, 1914, p. 11. 



A + orihos + aster = out of the regular, in reference to the completely 

 adambulacral na-ture of the interbrachial areas. 



