CALYPTOCRINIDiE. 349 



Eucalyptocrinus depressus s. A. :Miller. 

 Plate LXXXIII. Figs. 3, 4a, 4b. 



1S80. S. A. Miller ; Jouru. Ciuciu. Soc. Nat. Hist., Vol. III., p. 232, Plate 7, Figs. 1, la, 6. 

 1885. W. and Sp.; Revision Palsocr., Part III., p. 133. 



Of moderate size. Crown subcylindrical, twice as high as "wide, a little 

 tapering to the upper end, distinctly flattened and concave at the poles. 

 Dorsal cup almost twice as wide as high, the upper part of the radials and 

 the extreme ends of the first interbrachials forming the truncated bottom, 

 the upper part of the latter and the first costals gently curving upward, the 

 plates above parallel to those of the opposite side. Plates a little convex, 

 their surface apparently rugose. Lower concavity deeply and broadly fun- 

 nel-shaped, the basals constituting but little more than the bottom part. 



Eadials slightly longer than wide ; their upper half more or less hori- 

 zontal in position, and not visible from a side view ; the lower half forming 

 the slanting sides of the concavity ; their sloping upper faces rather long. 

 First costals twice as wide as long, a little shorter than the second at the 

 median line ; the upper end of the latter slightly truncated by the inter- 

 distichal. First distichals about a third smaller than the upper costals ; the 

 second half the size of the first, their upper angles quite obtuse ; the first 

 palmars very small and pentangular. First interbrachial subrotundate, as 

 long as wide, those of the second row as long, but together narrower than 

 the first, their upper ends rising to the base of the second arm plates. The 

 interdistichal has almost the form of the two upper interbrachials, but is 

 somewhat smaller. Partition walls nearly twice as long as the dorsal cup, 

 moderately thin, the outer edges rounded to near the top, then slightly widen- 

 ing and curving abruptly inward and somewhat downward, so as to form a 

 shallow depression around the summit. Their upper ends enclose five ratlier 

 large plates with a pentangular open space, the overlying plates being not 

 preserved in the specimen. The height of the calyx, as observed in the casts, 

 is about equal to the greatest width across the first distichals, and that of 

 the dorsal cup equal to that of the tegmen but narrower ; the tubular pro- 

 longation above almost as long as the rest of the calyx, widening at both 

 ends. Of the arms only the proximal plates are preserved, which are com- 

 paratively long. 



Horizon and Locality. — Niagara group; Cicero and Bridgeport, near 

 Chicajro, Ills. 



