CRIXOIDS AND BLASTOIDS. 193 



> [BORDER IX ADO AT A. 



BRANCH FISTULATA. 



FAMILY POTERIOCRIXID^E. 



GEXUS GRAPHIOCRIXUS. 



LONGICIRRIFER (nOV. 8p.) W. & Sp. 



PL XY, Fig. 12. Specimen with arms, from the anterior side. 

 PI. XTII, Fig. 14. The same from the posterior side. 



This species is of the type of Graphiocrinus (Scaphiocrinus) 

 wachsmuthi (M. & "W.). and Graphiocrinus (Scaphiocriuus) spino- 

 brachiatus (Hall), but differs from both in having cirrhi along 

 the upper portions of the stem. Besides, the former has a de- 

 cidedly bell-shaped calyx the upper part of the radials flanging 

 outward : also the brachials are much less constricted, the suc- 

 ceeding: arm plates considerably higher, and the outlines of the 

 arms less waving. G. spinobrachiatus has a more depressed 

 dorsal cup. the underbasals are covered by the column, it has 

 stouter arms, and these are covered with small spines. The 

 specimens are always of a light color. 



Calyx short, depressed, saucershaped, with slightly convex 

 sides; scar for the attachment of the column but slightly im- 

 pressed. Uuderbasals. although small as in almost every other 

 species of Graphiocrinus, extending slightly beyond the limits 

 of the column. Basals large ; four of them hexagonal, about as 

 wide as high : that of the azygous side considerably larger and 

 heptagoual, supporting upon its truncate upper face a large 

 anal plate, which extends far beyond the top of the radials, 

 and actually forms a part of the ventral tube. There is no 

 az3'gous plat P. 

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