428 Prof. F. J. Bell on a new Species q/ Antedoii. 



The following appear to be the diagnostic chai-actcrs of 

 this new species, which may be called 



Antedoa emendalrix. 



An Antedon of the " j:)a?»irtfa-group " of P. H. Carpenter, 

 in which the disk is exceedingly small ; the ceiitro-dorsal, 

 which is coextensive with its aboral surtace, has about 

 twenty-two pits, and the cirri have about twenty-five joints ; 

 the second half or distal set of these joints are spiny. The 

 arms are little more than ten in number or may be more than 

 twenty; the third brachial has a pinnule ; the second pinnule 

 is larger than the third ; the rays are free laterally ; the 

 second pinnule is stiff and styliform, has about twenty joints, 

 most of which have their distal edge projecting and serrated ; 

 the radials, distichals, and most prominent brachials have 

 marginal projections which are not very prominent ; the third 

 pinnule is only half as long as the second ; the third radial 

 is very little longer than the second. The third brachial is 

 a syzygy, and there is not another till the twenty-fifth joint. 



Colour purple-madder, the pinnules grey. 



Spread about loO millim. ; diameter of disk 6 millim. 



Hah. Mauritius. 



'IWb is really a very interesting species, inasmuch as the 

 comparatively large number (twenty) of joints in the second 

 pinnule makes it intermediate between Dr. Carpenter's set 

 (p. 225) of forms in which the second pinnule has from twelve 

 to eighteen much elongated joints and that in which the same 

 pinnule has twenty-live or more joints which are not specially 

 elongated. It has many points of resemblance to A. indica, 

 but its spinose cirri, its second pinnule, and its rare syzygies are 

 sufficient to distinguish it. An examination of Mr. Smith's 

 type of A. indica shows that in that species the rays have 

 marginal projections. It would be instructive to get a large 

 series of s[)ecinieiis of that species, of A. spicata and A. 

 tubercidata. At present we are in the stage of making species 

 oi Antedon^ and we must continue to do so till we have larger 

 and finer series before us. Then another part of our work 

 will begin ! 



EXPLANATION OF PLATE XVIIL 



Fiy. 1. Ahtedon vmcndafriv ; geueral view from the side. Nat. size. 



Fkj. '2. l'ortio:i of disk and anus. X •'{. 



Fit/. 3. I'ortiou of arm after la.-t axillary. X -. 



Fiy. 4. Second piunule. X 4. 



