42 f^- f>OTo : 



or luttîvjil spiiuî is the longest, find slightly gi-ositer than the supero-marginal 

 spine ; the imierniost spine of the three is the smallest, and is about half 

 the length of the latt^ral one. Tlici longest lateral spine is the third or 

 fourtli from the inteiTadial lin(s and measures about 5 mm., and the succeed- 

 ing ones decrease slightly in hnigth as they proceed outward. Tint rest of 

 the plate bejirs a few ■\\idt^ly spaced, small, miliary thornh^ts, some of wdiicli 

 at the bas(ï (»f the large spines are more (elongate than the others. There is 

 a iiak(ul suture-line between each plate. 



" Th(* adambulaci-al jüates are slightly longer than broad, and Avith only 

 a slightly convex margin towards ilu) furrow. Their armature consists of: — 

 (1.) A furrow series of six short, rather thick, cylindrical, obtusely x>ointed 

 spinelets, the inner pair slightly longer, and the outer on(^ at each extremity 

 veiy much smidler, than the rest; their posture reseml)les that of the fingers 

 of a hand held slightly concave. (2.) On ilw actinal surfaces of tlus x^late 

 are two robust, slightly tapering but obtusi^ly i^)ointed spinelets, ono. behind 

 tlu! other in the transverse median \hu\ The innermost stands close behind 

 tin* marginal .series, the outermost is slightly larger and is sul)e(|ual in size 

 to tlie innermost of the three spines on the infero-marginal plate. Two or 

 three minute miliary spinelets may lie present on the outer margin of the 

 pLite, but the rest of this plate has a naked appearance, and is only covered 

 with memlmine. 



"Tlu; mouth-])lates are ])()werful and slightly convex; («ich plaüi of tlu^ 

 united pair hilars on its frees margin six mouth-spines, the innermost being 

 the longest, most robust, and slightly compressed ; the others decrease as 

 they recede from tlu; mouth and become very short. On the actinal siu'face 

 of each plate art; thrcn; robust, tapering, secondary mouth-spines, two placed 

 so that a line joining them would run parallel to tlu; median suture, and 

 this liiu; is continued on the outer part of the ])lat(i by one; or two smaller 

 spinelets. The third large; spin(;let is i)hice;d o[)posite the interspace; between 

 the two large; spinelets abe)ve; mentioned, midway betwe;en them anel the 

 outermost of the marginal mouth-spines. 



" Tlu; actinal intenudial are;as are very small, not more than eight to 

 ten intermediate plates being present in each. The t\No innerme)st may bear 



