268 s. GOTO : 



the edge of the ra}'. On the lufero-marginal plates which abut against 

 aclambnlacral plates, the fringe is not present on that edge, but the four 

 innermost infero-marginal plates, that is to say, two on each side of the 

 median inteiTadial line, which abut against the actinal intermediate (ventral) 

 plates, have the fringe continuous round the inner end of the j^lates, and 

 on a few plates next succeeding a trace of the fringe is discernible, the 

 aboi-tion l^eing efiected gradually. Each infero-marginal plate bears a single, 

 small, compressed, comparatively broad, flat, truncate spinelet, scarcely 

 longer than the length of the plate ; it is articulated but adpressed to the 

 ray, dii'ected towards the extremity at a slight angle upwards, and it is 

 placed at the extreme margin of the actinal sm'face, consequently a little 

 below the upper edge of the infero-marginal plate, and stands close to its 

 aboral margin. Occasionally on one or two plates in the interbrachial arc a 

 second smaller and very much narrower spinelet may be present at some 

 distance from the marginal one, on the actinal sm-face, and likewise close 

 to the aboral margin of the plates. 



" The adambulacral plates are small, and, as seen with their armatm'e 

 when view^ed from above, appear subquadrate or rhomboid in form. Their 

 armature consists of a fmTow series of five or sis short, cylindrical, slightly 

 tapering spinelets, the outer ones rather smaller than the others, and all 

 radiating slightly apart at an angle over the furrow. The actinal surface of 

 the plate is covered with membrane, and is devoid of spinelets, but bears 

 round its margin, that is to say, on the tln-ee remaining sides, a series of 

 small, uniform, skin-covered, papilliform, obtuse spinelets, very much shorter 

 than the fmTOW series, and directed at an angle of about 45° to the plane 

 of the plate, towards the adjacent plate, whether this be an adambulacral or 

 marginal one. There is thus the appearance of a straight channel intsr- 

 vening betAveen the series of adambulacral plates and the marginal pla'^s 

 over wliich the series of skin-covered spinelets is directed, and the ad- 

 ambulacral plates are themselves distinctly and clearly spaced. Near the 

 middle of the aboral margin of each adambulacral plate is one comparative- 

 ly very robust, shoii;, stumpy, subconical spinelet, its posture suggesting 

 resemblance to a thumb in relation to the fiu'row series of spinelets, 



