KEVISIOlSr OF PALEOZOIC STELLEROIDEA. 



133 



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AGALMASTER INTERMEDIUS Schdndorf. 



Agalmaster intermedius Schondorf, Palaeontographica, vol. 56, 1909, pp. 82, 

 108, pi. 11, fig. 14; Jahrb. nassaiiisch. Ver. Naturk., "Wiesbaden, vol. 62, 

 1909, p. 30. 



From the Upper Coblenzian at Mielleii-on-tlie-Lalm, Germany. 



Genus RHENASTER Schondorf. 



Text fig. 10. 



Rhenaster Schondorf, Palaeontographica, vol. 50, 1909, pp. 05, 108, pi. 8, fig. 3; 

 pi. 10, figs. 1, 4. 



Remarks. — Rhenaster is a small form and dilTers from Xenaster, 

 Agalmaster, and Devonaster in the complete absence of all abactinal 

 accessory plates, allow- 

 ing the radial and sujDra- 

 marginal pieces to ad- 

 join one another closely. 

 Dorsal axillary disk 

 areas not completely 

 but almost absent, 

 supramarginals in the 

 main lying ^yholly upon 

 the inlramarginals and 

 the two columns of 

 plates together margin- 

 ing the rays. There 

 also are no accessory 

 plates of any kind on 

 the actinal side. Other- 

 wise the generic struc- 

 ture is that of Xenaster, except that in Rhenaster the firet pair of 

 interbrachial marginals are not ye I pushed so much orally and they 

 almost take part in margining the axils. Madreporite unknown. 



Genoholotype and only species (one specimen). — R. schwerdi Schon- 

 dorf, from the Lower Deyonic (Upper Coblenzian) at Dorrbachtal, 

 near Coblenz, Germany. 



Genus EIFELASTER Schondorf. 



Eifelaster Schondorf, Palseontographica, vol. 56, 1909, pp. 70, 108, pi. 10, figs. 

 7,8. 



Remarks. — This genus is very closely related to Rhenaster and 

 differs only in that there are small dorsal interbrachial areas between 

 the adjoining proximal portions of the supramarginal columns, and 

 these are filled with a small number of accessory ambital pieces. 

 The outer portion of these ambital areas is made up of the two basal 

 inframarginals that occupy the axils of the ventral side. 





o 



Fig. 10.— Rhenaster schwerdi, after SchOndgef. Schematic 

 arrangement of abactinal plates. symbols as in fig. 9. 



