MUSEUM OF COMPARATIVE ZOOLOGY. 31 



Amphiura patula sp. nov. 



.Plate XII. Figs. 335-337. 



Special Marks. — Five (sometimes only four) mouth-papillse on each side. 

 One tentacle-scale. Mouth-papillae squarish and crowded. Side mouth-shields 

 large and wide. Disk-scales small, irregular, and crowded. 

 , Description of an Individual (Station 156). — Diampter of disk 14.5 mm. 

 Width of arm close to disk, without spines, 2 mm. Five (sometimes only four) 

 squarish, crowded mouth-papillsa on either side, whereof the outermost and 

 innermost are largest ; besides these there is an odd one at the centre of the 

 apex. Mouth-shields small, rounded triangular, with a blunt angle inward. 

 Side mouth-shields short and stout, rudely triangular in shape, the inner angles 

 not quite meeting at the apex of the mouth-shield. Under arm-plates pentag- 

 onal, with inner angle sometimes truncated, outer edge slightly rounded, and 

 small re-entering curves on the lateral sides. Side arm-plates narrow, bent, not 

 very prominent, meeting above, but just separated below. Upper arm-plates 

 much broader than long, transverse oval, with outer and inner edges gently 

 curved. Disk flat, covered with thin, flat, irregular, crowded scales, among 

 which six small widely separated primary plates are with difficulty distinguish- 

 able. Radial shields large and broad, of a wide pear-seed shape, separated their 

 entire length by a narrow wedge of three or four scales. On the under surface 

 the scales are much finer and more rounded. Three short, round, bluntly 

 tapering arm-spines, the middle one larger than the others but not so long as 

 an arm-joint, and all placed low on the side arm-plate. Only one longer than 

 wide, somewhat swollen tentacle-scale, on the brachial side of the tentacle-pore. 

 Except that it has usually five, instead of four, mouth-papillse on a side, this 

 species stands related to A. dalea, from which it is distinguished by smaller 

 ann-spines, diff'erent under arm-plates, and coarser, more irregular scaling. 

 Color in alcohol, grayish. 



Station 156, 1975 fathoms, 4 specimens. 



Note, — The following are species previously known and now brought back by the " Challenger," 

 namely, A. squamata^ A capensis, A Otteri, A. dupHcata, A Studeri (A. antarctica), A. depressa. 



Amphiura capensis Ljn. 



AmpJiiura capensis. Of. Kong. Akad. Oph. Viv., 1866, p. 320. 

 Station 141, Lee's Point, Cape Town, 98 fathoms, 12+ specimens. 



Amphiura duplicata Lym. ^ 



Amphiura duplicata. 111. Catal., No, VIII., Pt. 2, p. 19. 



Station 56, 1,075 fathoms, 4 specimens. 



Quite common in less depths throughout the West Indies. A. duplicata is 



