OPHIUKANS OF UNITED STATES NATIONAL MUSEUM. 133 



Family HEMIEURYALTD^E. 



SIGSBEIA CONIFERA, new species. 



Plate 14, fig. 7; plate 17, fig. 6. 



Albatross station 2167 (type locality). May 1, 1884. Lat. 23 10' 40" N.; 

 long. 82 20' 30" W.; 201 fathoms; co. One specimen. 



Albatross station 2330. Jan. 17, 1885. Lat. 23 10' 48" N.; long. 82 19' 

 15" W.; 121 fathoms; fno. gy. co. One specimen. 



Type.C&t. No. 32307, U.S.N.M. 



Both specimens were fixed on branches of Stylaster filograna. 



I think we ought to refer to this species the small example described by Verrill 

 under the name of Sigsbeia murrhina (91, p. 72, pi. 2, figs. 1, la); indeed the 

 smaller of my two specimens is almost identical with it. 



In the larger sample, which comes from station 2167, the diameter of the disk 

 is 5 mm., and in the smaller, it exceeds 3.5 mm. ; the arms are more or less rolled up 

 and it is difficult to appreciate their length, especially in the larger specimen; in the 

 smaller one, they are hardly one centimeter long. 



I shall first describe the larger specimen. 



The disk is high and very thick, and its outline is pentagonal; the upper face is 

 strongly convex and it joins by a rounded edge the under face which is plane. 



The upper face is occupied, centrally, by plates which are few, small, unequal, 

 and irregularly polygonal; the space covered by them is of small extent. Distally, 

 there come first the radial shields which are large, triangular, longer than wide, 

 and the length of which very much exceeds half the radius of the disk. The two 

 shields of each pair are separated over their whole length, but they are nearer one 

 another distally than proximally and their internal edges are inclined toward 

 each other; the external or interradial side is, on the contrary, almost exactly parallel 

 to the corresponding side of the shield of the next pair. The two shields of each pair 

 are separated by a row which includes three chief plates; the distal plate is very 

 small and rectangular, the following one, which is larger, is triangular with rounded 

 angles; lastly, the proximal plate, which is very large, generally offers also a tri- 

 angular shape. This last plate, which proximally exceeds the end of the radial 

 shields, is much protruding and carries a large conical tubercle with a blunt point, 

 nearer to the distal angle of the plate; in one of the radii, this plate becomes double. 

 A like, but smaller tubercle, appears also on the middle of the second plate. Two 

 or three other very small plates fill up the interval between the last two plates. 

 The interradial spaces are occupied by a row of narrow plates which generally 

 amount to three; the first one is longer than wide, and the third one which is widened, 

 occupies the margin of the disk. All the plates of the upper face of the disk appear 

 to be firmly jointed to one another and their surface is covered with minute granules. 



The upper face of the disk is beset by a small number of unequal and polygonal 

 plates, among which are seen the elongated and narrow genital plates. The genital 

 slits extend out on a small part of the length of these plates; they are very short 

 and retain the same width over their whole length, without showing inwardly 

 that widening which exists in S. murrhina. 



