170 Natural History Bulletin. 



covered with scale-Hke plates, large, triangular, radial shields, 

 a fringe of scale-like genital plates extending around over the 

 bases of the arms, and very long arm-joints. The actinal sur- 

 face was peculiar in the round, scale-fringed pores for the 

 tentacles, the verv large mouth-shields, the slender side mouth- 

 shields, and three curiously shaped mouth-papilla?. There 

 were three very short arm-spines, the middle one being the. 

 shortest. Another species closely allied to the last has much 

 longer arm-spines and differently shaped arm-plates. They 

 came from comparatively shallow water. A small species of 

 Amphiiira has two mouth-papilla?, one tentacle-scale, and six 

 unequal arm-spines. Depth about one hundred and thirty 

 fathoms. The genus Opliiocoiua is represented by a single 

 species and a single specimen. The disk is closely covered 

 with stumpy nodules or blunt spines, there are two tentacle- 

 scales, five or six arm-spines, five mouth-papilla?, and very 

 numerous, closely set, tooth-papilla?. The mouth-shield is very 

 large and roughly heart-shaped. A species of Ophiocamax 

 dredofed from near the one-hundred-fathom line shows an 

 approach to Asiyop]i\ton in its spiniform mouth-papilla" and 

 tooth-papilla\ although in other respects it is a typical ser- 

 pent-star. The disk is svmmetricallv studded with spinulose 

 stumps, and the radial shields are small and triangular. There 

 are nine long arm-spines which bear spinelets over their entire 

 surface instead of along the sides only. A still nearer approach 

 to the basket-fish type is found in a species of Ophioniyxa, 

 which has four arm-spines that are larger and sharper than in 

 O. flaccida. Our specimens came from a depth of twenty to 

 sixty fathoms. 



But the greatest surprise revealed by our dredges and 

 tangles wliile working on the Pourtales Plateau was tlie great 

 (juantity of Astrophytid.^^, both simple-armed and branched. 

 As in the preceding group, we were constantly struck with 

 the tendency on the part of single species to occur in great 

 nvmibers on definite spots of the sea bottom. Especially was 

 this true of the simple-armed forms, a group which none of 

 us had seen before our experience off the Cuban coast. On 



