2 PROCEEDINGS U'S THE NA'IIOXAL MUSEUM. vol.65. 



The history and characters of the genus Balanocrinus have been 

 exhaustive!}^ discussed by Dr. F. A. Bather, of the British Museum, 

 in connection with a rediscription of the two leading species from 

 the middle and upper Eocene of the London clay and the Num- 

 mulitic beds of Biarritz, France ; ° and reference should be had to 

 this important paper for the fullest information upon the subject. 



The Haitian material consists of 24 stem-fragments, ranging from 

 a maximum length of 41 mm. down to short pieces of only two or 

 three columnals. The longer pieces from 25 to 41 mm. in length 

 have 9, 10, 11, 12, 14, and 16 columnals, the number 14 being the 

 most frequent. It seems probable that some of these represent com- 

 plete internodes, or intersj^zygia, although in none of them are two 

 terminal syzygial faces perfectly shown. The preservation of the 

 specimens is mostly rather poor, the surfaces being more or less 

 covered with carbonate of iron and the edges at the joints often 

 considerably frayed; but enough remain intact in several instances 

 to disclose the joint faces characteristic of the genus. 



Comparison is naturally suggested with the Italian species of 

 nearly equivalent horizon, but in order to establish the record it 

 will be best first to describe the Haitian form as a new species. 



BALANOCRINUS HAITIENSIS. new species. 



Plate 1, figs. 1-lOa. 



Known only from stem-fragments. One of the two longest is 41 

 mm. in length, tapering from 7 to 6 mm. in diameter, composed of 

 16 columnals averaging about 2.5 mm. in height (fig. 1) ; this prob- 

 ably embraces a complete internode, of which the terminal ossicles at 

 either end were cirrus bearing, the evidence of which is obscure, but 

 is reinforced by comparison with the syzygial face in some other 

 specimens. Another of nearly the same length (fig. 8) contains 12 

 columnals 8.5 to 9 mm. in diameter, averaging 3 mm. high, plus a 

 lower one at each end; one of these is clearly the epizygal, having 

 two cirrus-facets at adjacent radii pointing obliquely upward (drawn 

 with this end uppermost for better lighting), and faint indication 

 of a third one opposite to these two; the corresponding columnal 

 at the other end shows indistinct traces of three cirrus facets alter- 

 nately placed. Two other pieces (not figured), 39 and 35 mm. in 

 height, have 16 and 14 columnals, respectively, of which the terminal 

 faces may be syzygial. thus giving 14 and 12 ossicles to the internode; 

 these terminal ossicles seem rather shorter than the others, but 

 cirrus-facets are not seen, A fifth piece of 33 mm. in length has 14 



6 British Fos.sil Crinoids, XI, Dalanocrinus of the London Clay. Ann. and Mag. Nat. 

 Hist., ser. 8, vol. 20, Dec. 1017, pp. 385-407. 



