294 DISCOVERY REPORTS 



Lyman is a very heterogeneous assemblage, and his O. abnormis does not agree with the 

 typical Ophiocnida, which is characterized by having three equal-sized mouth papillae, as 

 in Amphiodia. The mouth papillae of the species abiiormis are exactly as in Amphipholis, 

 the outer papilla being very broad and flat, and Verrill therefore transferred this species 

 to the genus Amphipholis, in which he is followed by H. L. Clark. But exactly the same 

 type of mouth papillae is found also in the genus Ophiosfigma of Liitken. The question 

 is then how to distinguish between Amphipholis and Ophiosfigma. As a matter of fact, 

 I do not find any other distinction mentioned between them than the existence of spines 

 on the disk in the latter, these being absent in Amphipholis. This is a rather unimportant 

 character, and we might thus far maintain Amphipholis and Ophiosfigma to be identical. 

 However, this would lead to the very deplorable result that Ophiosfigma as the older 

 name would have to supplant the very well known and now generally accepted name 

 Amphipholis. I therefore think it necessary to maintain the name Ophiosfigma for the 

 group of species of the Amphipholis type with spines on the disk, just as Ophiocnida is 

 kept for the species of the Amphiodia type with spines on the disk. Also the peculiar 

 spine-like tentacle-scales appear to form a valuable generic character of Ophiosfigma. 



This species has separate sexes and is apparently not viviparous; I have not seen 

 female gonads, the only two adult specimens, 2-5-3 mm. in diameter of disk, being 

 males, the others not yet having the gonads developed. 



The species was not hitherto known from Ascension, but being found in the West 

 Indies and on the African coast, it was to be expected that it would occur there. 



Amphioplus acutus, n.sp. 



(Plate VIII, fig. 14) 



St. 180. II. iii. 27. Schollaert Channel, Palmer Archipelago, 160 m. 5 specimens. 



St. 181. 12. iii. 27. Schollaert Channel, Palmer Archipelago, 160-335 ^n- Several specimens. 



St. 182. 14. iii. 27. Schollaert Channel, Palmer Archipelago, 278-500 m. 4 specimens. 



St. 190. 24. iii. 27. Bismarck Strait, Palmer Archipelago, 315 m. i specimen. 



Diameter of disk up to 9 mm. ; arms slender, about seven to eight times the diameter 

 of disk. The outline of the disk is usually pentagonal, the interradial edges straight or 

 at most gently concave. 



The disk is covered by rather large, imbricating scales, among which the primary 

 plates are not very distinctly seen. In the interradii the scaling of the underside 

 generally continues some distance on the dorsal side, forming a rather well limited area 

 because the scales here imbricate in the opposite direction to that of the scales of the 

 dorsal side of the disk. The radial shields are narrow, straight, diverging, widely 

 separated in their whole length; they are a little more than one-third the disk radius. 

 The ventral interradii are covered throughout by small, more or less rounded scales, 

 much finer than those of the dorsal side of the disk. 



Buccal shields almost quadrangular, with inner and lateral angles almost right, but 

 the distal angle rounded ; the sides, particularly the inner ones, straight. The madre- 

 porite is usually conspicuous, with an irregular circle of very distinct pores, each on a 



