REPORT ON THE OPHIUROIDEA. -Js:; 



from without inward, and having the small, peg-like scale attached near its outer end. 

 Colour in alcohol, pale straw. 



Station 241.— June 23, 1875 ; kit. 35° 41' N., long. 157° 42' E. ; 2300 fathoms ; red 

 clay. 



This species, well distinguished from others, is remarkable for the great depth at which 

 it lives. The genus is usually found not far below the 100 fathom line, and 500 fathoms 

 may be considered deep for it. 



Ophiocreas cedipus, Lym. (PI. XXXI. figs. 5-8 ; PI. XLVI. fig. 1). 



OpMocreas cedipus, Lym., Bull. Mus. Comp. Zool., vol. vi., part 2, p. 65, pi. xvi. figs. 443-446, 

 1879. 



Arms about twenty times the diameter of disk, and slender, except the base, which is 

 swollen above, and contains the ovaries. 



(Type specimen from Station 344.) Diameter of disk 12 mm. Length of arm about 

 250 mm. Arm much swollen for the first four or five joints next disk, where its width 

 is 3'5 mm., then suddenly shrinking to 2 mm. with a height of 2 mm. There are 

 numerous small, flattened grains extending along the sides of the mouth angles, above 

 the second mouth tentacle. Eight or nine broad, flat teeth, with well rounded cutting 

 edges, the two lowest being much narrower and peg like. On removing the skin the 

 mouth shield is seen to be very small, a little longer than wide, with ends much rounded. 

 Side mouth shields very large, much longer than wide, somewhat swollen, meeting within 

 where they are narrowest. Under arm plates composed of two or more small pieces. 

 Side arm plates swollen, meeting below, and at the base of the arm, joined to thick, 

 narrow, ridgedike upper arm plates, which arch upward, and nearly or quite meet on the 

 median line. Disk angular and flat, with re-entering marginal curves. Eadial shields 

 narrow and highly arched, not quite meeting in the centre, covered with thin skin, which 

 under the microscope is seen to be set with fine points. Genital openings large and 

 wide, occupying the whole height of the disk. Where the skin is removed the genital 

 plate is seen to be long, very broad and thick, tapering inward ; the genital scale is small 

 and peg like. At base of arm there is only one tentacle scale ; beyond there are two, 

 the upper one very small, and spiniform, the lower one enclosed in a thick club ended 

 skin bag. 



On opening the singular swelling on the upper side of the base of the arm, it is found 

 to be a pouch full of large egg clusters, which are about '7 mm. long. In fact, the 

 ovaries are in this species thus pushed beyond the disk, somewhat as in Starfishes. 



Colour in alcohol, pinkish or yellowish-brown. 



Station 214.— February 10, 1875; lat. 4° 33' N., long. 127° 6'E. ; 500 fathoms globi- 

 gerina ooze. Station 343.— March 27, 1876; lat, 8° 3' S., long. 14° 27' W.; 425 fathoms; 

 coral. Station 344. — April 3, 1876; off Ascension Island; 420 fathoms; hard ground. 



