AMPHIURA MAGELLANICA. 19 



pines, and which h.is four mouth-papillas on a side and two tentacle-scales. 

 It also resembles A. ptilchella, but diifers from it by being naked below and 

 having no prominent primary plates. 



AmpMura magellanica i Ljn. 



Ljungjian. Ophiuroidea Viventia, 320. 



Tlie specimens agree well with the description, except that, 1st, the upper 

 arm-plates are rather rounded fan-shape than " oval " ; and, 2d, the arm- 

 spines are but feebly " thorny." The originals, at Stockholm, are in poor 

 preservation ; they stand near A. capensis, as do also these specimens, which, 

 however, differ from it in having longer and more slender arm-spines. The 

 largest had a disk T""' in diameter, and arms four or five times as long ; 

 there were seven slender tapering arm-spines, increasing in length from 

 above downward. Small radial-shields wholly separated by a row of scales. 

 One tentacle-scale. One mouth-papilla on either side, besides the thick 

 pair just under the teeth. The species is viviparous. 



Hassler Expedition ; Lat. 41° 40' S., Long. 63° 13' W., N. E. Patagonia, 30 

 fathoms. 



Amphiura duplicata sp. nov. 

 PI. V. f. 78. Outline 87. 



Special Maries. — First (rudimentary) under arm-plate transversely divided 

 in two. Radial shields separated by a wedge of scales and only touching at 

 their outer ends. 



Descriptimi of an Individual — Diameter of disk, 4™". Width of arm with- 

 out spines, 1.1™". Length of arm, 20"""'. Mouth-papillae, seven ; thi'ee on 

 each side, which are stout, blunt, spiniform, and 



Fig. 87. 



all on the mouth-frames, and one under and simi- 

 lar in shape to the teeth. Mouth-shields short, 

 hearf^shape, with an angle inward ; length to 

 breadth, .8 : .8. Side mouth-shields long, narrow, 

 slightly curved, wider without than within, where 

 they meet. Under arm-plates ; the first is trans- 

 versely divided, the inner half reaching into the 



mouth-slit, while the outer joins the side mouth-shields on each side. Second 

 plate hatchetrshaped, with an angle within, strongly re-entering curves on 



