15S COLLECTIONS FROM MELANESIA. 



Arm about 30 millim. long, cirri 7 millim., diameter of disk 

 3*5 millim. 



Colour creamy white, in spirit. 



Port Jackson, 0-5 fms. 



The above description was originally drawn up from the single 

 specimen received from the ' Alert,' which in spirit had a creamy- 

 white colour and appeared to be hardly mature. Since its arrival 

 the Museum has acquired specimens from Prison's Bay, which are 

 no larger and are a little darker or grey in colour ; these specimens, 

 of which I have been able to examine a number, bear witness to their 

 maturity by the presence of a large number of ova attached to the 

 pinnules. 



6. Antedon bidens. (Plate XI. figs. A, a-c.) 



Centrodorsal prominent ; about 20 cirri, with about 20 joints, a 

 number of which have two minute processes on their dorsal side ; 

 the penultimate spine is small ; none of the joints are distinctly 

 longer than broad, but a number of them have a shallow lateral ex- 

 cavation along their distal edge. 



First radials just visible; second very wide, in contact; third almost 

 triangular, not quite twice as long as the second, and forming a 

 convex protuberance with it. Ten arms. First brachials in contact, 

 a little wider on their outer than their inner side, as are also the 

 second brachials, which form with the first a convex protuberance ; 

 the third brachials, which are syzygies, have a sharp distal edge, as 

 have the succeeding joints ; these soon become wedge-shaped, and 

 form a strong overlap on either side alternately ; after some time 

 this diminishes, and the more terminal joints of the arm form rather 

 bead-like swellings on either side. 



Syzvgies 3, 9, 14 ; 4-6 joints between the succeeding syzygies. 



The first pinnule is very stiff and long, with the most proximal 

 joint the longest ; it is placed on the second brachial, has some 12 

 joints, of which the more basal are much longer than broad, and 

 which are also stouter than those on the sixth brachial, which, 

 again, are a little stouter than those on the fourth. The pinnules 

 then gradually diminish in size, and then again increase further 

 out. 



The arms are stiff, and somewhat compressed from side to side : 

 they are about 45 millim. long ; diameter of disk 5 millim., of centro- 

 dorsal 3-3 ; length of cirri about 8 millim. 



The original colour was probably purple. 



Torres Straits. 



7. Antedon loveni. (Plate X. figs. A, a-e.) 



Centrodorsal large, as large as the disk, excavated in the centre, 

 with about 20 cirrus-sockets (cirri lost). 



First radials just visible, second oblong with a convex median 

 protuberance along their distal edge ; axillary pentagonal, not a 



