150 



BULLETIN OF THE 



thorny arm-spines ; lengllis to that of an arm-joint 1.3, 1.3, 1, 1, .6, .4, .4 : .5. 

 Bej'ond the basal joints there are but six spines, whereof the upper are shorter 

 thau those described above. One very small, narrow, pointed tentacle-scale. 

 Color in alcohol, nearly white. 



Station 142, Agulhas Bank, 150 fathoms, 4 specimens. 



0. vicarius beai's a general resemblance to this species, but is distinguished 

 by naiTower side mouth-shields and by long and numerous disk-spines. 



Ophiothamnus vicarius Ltm. 



Ophiothamnus vicarius. Bull. Mus. Comp. Zoul. I. Ko. 10, p. 342. 1869. 

 Station 23, 450 fathoms, 8 specimens. 



OPHIOMITRA. 



TABLE OF SPECIES HEREIN DESCRIBED. 



Radial shields depressed ; along 

 their outer corners and along 

 margin of disk are large, some- 

 what swoUen plates, wider than 

 long ; the median interbracliial 

 space filled by smaller plates or 

 scales. Five to eight ana-spines. 

 In alcohol, eacli interbracliial 

 space contracts, formiiig a de- 

 pression or crease. 



Mouth-papillae inclined to strong spiniform. 

 Arm-spiues stout. Outer edge of under arm- 

 plates swollen, and in large specimens turned 

 down. Five or six arm-spines. 



Eight spines, less stout than in 0. plicata, 

 and disk-scales finer. Tentacle-scales jagged or 

 thoniy. 



Radial shields widely separated, the large 

 disk-jilates running along their entire interbra- 

 cliial margin. Under ann-i>lates not swollen. 

 Under arm-spine thickened, and beyond middle 

 of arm bent. 



Outer edge of under ann-plates swollen. ' 

 Tentacle-scales thorny. Under arm-spines 

 straiglit. 



Upper ann-plates long and slender. Marginal 

 disk-i)Iates large, and mucli swollen. Central 

 disk-scales line, and bearing minute thorny 

 . stumps. 



• 0. plicata. 



Sarsii. 



0. chelys. 



. carduus. 



■0. dipsacos. 



Ophiomitra plicata sp. nov. 



Plate VIII. FlgB. 209 - 212 ; Plate IX. Figs. 233 - 235. 



Special Marks. — ]\Iouth-pfipilhc thick, spiniform. Arm-spines five or six, 

 stout and cylindrical. Outer edge of under arm-plates swollen and in large 

 specimens turned down. Disk-spines stout and conical. 



Description of an Individual (Station 205). — Diameter of disk 16 mm. Length 

 of arm about 132 mm. Width of arm without sj)ines 5 mm. !Mouth-papilliB 

 nine to each mouth-angle ; stout, spiniform, about ('([ual, blunt. Teeth similar 

 to moutli-pai»illie, but shorter and ilatter. Minith-shields small, as long as 

 broad, with an irregular outline ; the outer margin more or less thickened and 

 curled downwards ; lengtli to breadtli 2 : 2. Side mouth-shield broad, thick, 

 and closely joined to the surrounding parts. Under arm-plates broader than 



