REPOET ON THE OPHIUROIDEA. 149 



AmpJdura tumida, Lym., Bull. Mus. Comp. ZooL, vol. v., part 9, p. 225, pi. ii. 

 figs. 28-30, 1878. 



West Indies ; 321 fathoms. 



Amphilepis. 

 AmpMlepis, Ljn., Oph. Viv. Of. Kong. Akad., 1866. 

 Disk flat, covered with rather large naked overlapping scales and stout radial 

 shields. Large teeth. No tooth papillae. Mouth angle wide, of medium length, and a 

 few (usually six) small, unequal, scale-like mouth papillae. Second mouth tentacles 

 enclosed between first under arm plate, outer end of side mouth shield, and outer mouth 

 papilla. Arm flat, even and slender. Arm spines few (usually three) short and regular. 

 Two genital openings in each interbrachial space. 



The disk scales and stout radial shields are much coarser than in most Amphiurae, as, 

 indeed, is the general structure. Especially are the jaws and mouth frames stouter, more 

 flaring and proportionately wider, while the nerve ring is covered by a substantial peris- 

 tomial plate in a single piece of a long oval form. The genital plates have a very long 

 head of a cylindroid form, which suddenly passes into a short flat shaft, just where a 

 short, flat genital scale is joined, so that the two pieces give somewhat the efiect of a 

 lobster's claw. The arm bones are similar to those of the Amphiurae, and those nearest 

 the disk margin have a forward projection of the upper surface. (See PI. XL. fig. 19.) 



AmpMlepis norvegica, Ljn. (PL XL. fig. 19). 



AmpMlepis norvegica, Ljn., Oph. Viv. Of. Kong. Akad., p. 322, 1866; Dr. Goes, Oph. Of. Kong. 



Akad., p. 632, 1871. 

 Amphiura norvegica, Ljn., Tillagg Skan. Oph. Of. Kong. Akad., p. 363, pi. xv. figs. 3-3d, 1864. 



So far as one may judge, without having a proper series, these are the adult of 

 Ljungman's original. They have the disk as large as 9 mm. The radial shields are 

 pretty large and separated, and there is no tentacle scale. 



Station 45.— May 3, 1873 ; lat. 38° 34' N., long. 72° 10' W. ; 1240 fathoms; mud. 

 Station 46.— May 6, 1873 ; lat. 40° 17' N., long. 66° 48' W. ; 1350 fathoms ; mud. 



AmpMlepis patens, Lym. (PI. XIX. figs. 1-3). 



AmpMlepis patens, Lym., Bull. Mus. Comp. ZooL, vol. vi., part 2, p. 34, pL xii. figs. 

 338-340, 1879. 



Disk flat, round and smooth. Mouth angle large with three wide mouth papillae on 

 each side. Second pair of mouth tentacles encircled by hard parts of the mouth. 



Diameter of disk 11 mm. Width of arm near disk 2 mm. Mouth papillae broad 

 and irregular ; on either side of the large prominent mouth angle, at the outer corner, 

 are two or more or less closely joined ; and, at the apex, a larger pair which, through 



(zOOL. CHALL. EXP. — PART XIV. 1882.) 20 



