118 BULLETIN OF THE 



Avhich form above the base of tlie arm two irregular transverse rows, three or 

 four in each row. Three small peg-like arm-spines about one third as Ion" as 

 a joint. Color in alcohol, pale gray. 



Station 171, 600 fathoms, 1 specimen. * 



Ophiomusium granosum sp. nov. 



Plate I. Figs. 12, 13. 



Special Marks. — Most of the lower interbrachial space outside the month- 

 shield is occupied by broad genital scales and a great central plate. No^ 

 under arm-plates beyond the thiixl. Five short, sharp, well-marked arm- 

 spines. The great lower interbrachial plate is separated by a si^uare one 

 from the mouth-shield. Margin of disk set with small points. 



Description of an Individual (Station 237). — Diameter of disk 10 mm. 

 Width of arm, without spines, close to di3k 2 mm. Mouth-papilla) very 

 closely soldered together, forming a ridge. Mouth-shields triangular, with 

 an acute angle within, and the outer edge curved. They bear minute spines. 

 Side mouth-shields long and narrow ; meeting within, where they are nar- 

 rowest. Genital scales large, angular, longer than wiile. First under arm-plate 

 semicircular ; second and third triangular, with an acute angle inward. Side 

 arm-plates minutely tuberculous, meeting broadly above and below, and nearly 

 covering the entire arm beyond the disk. Upper arm-plates n)inute, triangular, 

 ■with acute angle inward. There are no tentacle-scales. Disk covered with 

 closely soldered plates, having decided furrows between them ; the microscopic 

 tuberculation usual in the genus is very coarse, and rises near edge of disk into 

 'small points. The margin is occupied by a large, angular, swollen plate, cov- 

 ered with points, which connects the radial shields with the genital scales, and 

 is united to the mouth-sliield by a smaller rectangular plate, also carrying 

 points. Radial shields pear-seed shape, diverging inward, where they are 

 separated by a triangular plate. In centre of upper surface of disk is a large 

 pentagonal primary plate, surrounded by five others, quadrangular, and con- 

 nected with the radial shields by five rudely triangular pieces ; in each inter- 

 brachial space above are two quadrangular plates, besides that of the mai^dn. 

 Arm-spines five in number, occupying the whole edge of the side arm-jjlates ; 

 they are short, rounded, and delicately tapering. Color in alcohol, gray. 



Station 237, 875 fathoms, 4 specimens. 



Ophiorausium pulchellum Ww. Tiiom. 



Yoj'age of the "Challenger." The Atl:uiti(!, A'<.1. H. p. 07, Figs. IS, 19. 



Plate V. rigs. 144, 143. 



Special Marks. — Primary plates biuuing a larger central tubercle ; second 

 pair of side arm-])lat(,'s wide, and flaring below ; l>)wer interbrachial space 

 occupied aliiKi.st wholly by large genital scales, and a marginal plate like a 

 tubercle. 



