340 PEOF. r. J. BELL ON CEINOIDS PROM THE SAUTJL BANK. 



species (A. incerta and A. longicirra) should be united. The other 

 distinctive characters, however, on which Carpenter insists 

 seem, so far as A. longicirra is concerned, to be constant, and 

 with the present condition of our collections the species can still 

 be readily distinguished. 



Antedon Wood-Masoni, sp. n. (PL XXIII. & PL XXIY., 

 fig. 1.) 



This new species belongs to Carpenter's Spinifera-gvou-p ; 

 that is, it is bi-distichate and has some of the basal joints more or 

 less wall-sided. As it has more than thirty cirrus-joints, the more 

 distal of which are spiny, the first pinnule as long as or longer 

 than the second, and the cirri not arranged in rows on the centro- 

 dorsal, it stands nearest to A. duplex (P. H. C. MSS.) and A. Imi- 

 tanica. The former of these has from 30-40 cirrus-joints, the 

 latter 50 ; the present would appear to have from 35 to 45 ; the 

 radial axillaries are short and wide as in A. lusitanica, and there 

 is no noticeable expansion of any of the joints of the pinnules. 



The following may serve as a specific diagnosis : — 



A member of the Spinif er a- gromp, and falling under the same 

 subdivision as A. duplex and A. lusitanica. Centrodorsal rather 

 laro-e, but not columnar, the central portion free of cirrus-sockets ; 

 about 18 cirri, with 35-45 joints ; these begin to be spiny 

 at about the tenth joint, and the spine, though not large, is 

 quite well marked. First radials hidden, the second much 

 wider than long, slightly concave on its distal side ; the axillary 

 wide with two slight concavities for the reception of the first 

 distichal, which again is much wider than long ; the distichal 

 axillary of much the same shape as the radial ; the two visible 

 radials and the distichals have a median linear tubercle. 



20 arras. Basal joints with fairly regular sides ; the third a 

 syzygy ; then one, ordinarily, on the 12th or 14th joint ; then not 

 another for 12 or 14 joints. The arm-joints gradually become 

 triangular, flattened from side to side, and provided with a median 

 ridge. The pinnules are styliform, but short and with simple 

 joints ; they increase somewhat in length nearer the end of the 

 arm. 



Diameter of disk 6 millim. Length of arms 110 millim. 



Colour white, with faint patches of brown here and there. 



Kab. Sahul Bank, North Australia. 



In Coll. B.M. and Ind. Mus., Calcutta. 



