BATOCRINID^. 517 



tliem angular above, the other two truncated, one of the latter support- 

 ing the first anal, the other the anterior radial. Eadials .generally' wider 

 than the two costals. Distichals two when palmare are represented, but 

 five or more if these are wanting. In the latter case a stout pinnule 

 from the second distichal takes the place of an arm, and the plate above 

 is not pinnule- bearing. Arms long and slender, composed of cuneate single 

 pieces. Pinnules stout, given off alternately from opposite sides. Inter- 

 brachials, interdistichals, and interpalmars numerous ; the anal side wider, 

 with a longitudinal row of anal plates, followed by a strong ridge. Ventral 

 disk composed of minute irregular pieces. Position of anus unknown. Col- 

 tnnn quadrangular ; axial canal small, pentangular ; the angles interradially 

 disposed. 



Distribution. — Upper part of the Hudson River grouj) of Ohio. 



Remarhs. — Compsocrinus Harrisi, the type of the genus, was originally 

 described by Miller trader Gli/ptocrinus, and nothing was said of the first 

 anal forming a part of the radial ring. Neither was this noticed in 1883 

 in Miller's generic description of Compsocrinus, but his diagram shows it, and 

 he also stated it in the revised specific description. The structure was over- 

 looked by us in 1881 when we referred the species to Mariacrinus. Since 

 then we have discovered that Miller's " Glijptocrinns " mamiensis also belongs 

 to this genus, having a quadrangular stem, and four basals supporting six 

 plates. 



Compsocrinus Harrisi S. A. Miller. 

 Plate XXI. Figs. 8a, b. 



1S81. Gli/ptocrhms Harrisi — S. A. Miller ; Joui-q. Cincin. Soc. "Nat. Hist. Tol. TV. (April number)i Plate 



1, Figs. 4, 4». 

 1883. Compsocrinus Harrisi — S. A. Miller; ibid,, Vol. VI., p. 234, Plate 11, Figs. 4, ia. 

 1885. Mariacrinus Harrisi — W. and Sp. ; Revision Palseocr., Part III., p. 104. 



A small highly ornamented species. Calyx higher than wide ; rapidly 

 expanding to the middle of the first costals, less spreading above ; interradial 

 areas depressed. Surface covered with prominent ridges, arranged into well 

 defined stars with intervening triangular depressions. Radial ridges wide 

 and prominent, occupying one half the width of the plates, rounded on the 

 back, and wider at the ends of the plates than at the middle. The ridges 

 toward the interbrachials lower and flattened at the top, but like the radial 

 ridges stoutest near the suture lines, a peculiarity which is also found at the 

 interdistichals and interpalmars. 



