MELOCRINID^. 289 



Basals large, forming a rounded cup, with a narrow columnar attacHment. 

 Radials unusually large, fully four times the size of the costals, and about 

 three times as long ; very little sloped to meet the first interbrachial. First 

 costals somewhat larger than the second. The two proximal palmars incor- 

 porated into the calyx, the others free. Arms ten. Interbrachials compar- 

 atively small, one and two at the regular sides ; the anal side wider, and 

 composed of three plates in the first row. Ventral disk constructed of small 

 irregular pieces. 



Horizon and .Locality. — Same as last. 



Bemarks. — Hall's figures 5 and 6, on Plate 13 of the 28th Rep. N. Y. 

 State Museum, are incorrect and misleading. The first costals are represented 

 twice as large as they actually are, and the ornamentation is also somewhat 

 different in the specimens. In the 20th Rep. of the same series, Plate 10, 

 Fig. 1, Hall figures a cast from the Niagara group of Racine, Wise, described 

 on page 379 under the name of Aetinocrimis {Saccocrinus) semiradiatus^ which 

 may possibly be a large example of this species. 



Macrostylocrinus granulosus (Hall), 

 Plate XXII. Figs. 15a, h. 



1879. Macrostylocrinus striatus, var. granulosus — Hall ; 28tli Rep. N. Y. State Mus. Nat. Hist. (Mu- 

 seum edit.), p. 129. 

 1885. M. striatus, var. granulosus — W. and Sp. ; Revision Palseocr., Part III., p. 103. 



A more slender species than the preceding. Dorsal cup obconical; its 

 sides nearly straight, spreading gradually and uniformly upwards; cross- 

 section at the top of the costals decidedly pentangular; the basals and all 

 plates following the rays marked by broad, rounded ridges. Another promi- 

 nent ridge passes from the anus downward to the middle of the proximal 

 anal plate, where it bifurcates to adjoining radials. Narrower ridges connect 

 the radials laterally, and form a well defined boundary line between the 

 upper and lower portions of the dorsal cup. The general surface is covered 

 by fine wrinkles and indistinct striae ; those following the radials and costals 

 longitudinally arranged, the others meeting within the middle of the plates. 



Basals and radials smaller than in the preceding species ; the latter plates 

 about as wide as long, subquadrangular, and but very little sloped at the 

 upper corners. First costals less than two thirds the length of the radials, 

 and considerably narrower; second costals shorter and narrower than the 



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