EEPORT ON THE OPHIUROIDEA. 21 



Ophiozona. 

 OpMozona, Lym., 111. Cat, Mus. Comp. Zoo]., Xo. i., 1865. 



Disk covered with radial shields and stout scales. The larger mingled with lines of 

 smaller ones. Over the base of each arm, a small notch in the disk. Genital scales thick 

 and conspicuous. Teeth. No tooth papilla3. Numerous even, close-set mouth papillae. 

 Side mouth shields wide, and nearly or quite meeting within. Few (2-5) short arm spines 

 usually arranged not along the outer edge of the side arm plates but on their outer corner, 

 so that the spines stand at an angle with the arm. No supplementary pieces to the upper 

 arm plates. Two genital openings, beginning at the sides of the mouth shields. 



The skeleton presents a stout, flat, somewhat curved genital plate with a clubbed 

 end, and a genital scale of equal length which runs below it, and is for some distance, 

 soldered to it. The peristomial jjlate is thick and swollen; sometimes single, and some- 

 times divided in two. Of the discoid arm Ijones, those within the disk are scarcely 

 grooved on their edges, while those beyond have grooves and thinner wings. Seen from 

 within the upper disk is set with stout, strongly overlapping plates, and oblong separated 

 radial shields. (See PI. XXXVII. figs. 13-15.) 



Table of Species op Ophiozona. 



, K • r Arm spines nearly as lone as side arm plates : lowest one ) ^ ■, ■ 



4-5 arm spmes , jo i > k Qpjuozona invpressa. 



Small separated J longest, . . . . . .) 



radial shields, . < • i i i i. /^ 7 • -^ 



' l,Ai-m spines equal and very snort, .... Ophiozona pacijica, 



I-Eadial shields large and touching, . . . OpMozona nivea. 



4 arm spines, . ^ Radial shields large and separated. Two scales on first two ) 



[ tentacle pores only, "^ OpMozona insulavia. 



r, ■ ( Large radial shields, hearing a bhmt spine on their outer ) ^ , . . ,1 . 



3 arm spines, . ) ° > & 1 i Ophiozona tessellata. 



( end, . . . . . . .J 



o 



O 



r 



2-3 arm spines. 



I 



e ) 

 > Ophiozona antillarum. 



Radial shields small and separated, . . . OpMozona stellata. 



Large pointed radial shields nearly touching at their middle 

 point, ..... 



Large, oval, well separated radial shields, . . . Ophiozona depressa. 



Radial sliields wide and touching. First side arm plates \ 



very ■wide, and extending into centre of interbrachial \ Ophiozona (?) dvhia. 

 space, . . . . . . ) 



Ophiozona impressa, Lym. (PL XXXVII. figs. 13-15). 



Ophiolepis impressa, Ltk., Addit. ad Hist., part 2, ji. 101, jil. ii. fig. 3, 1S59. 

 Ophiozona impressa, Lym., 111. Cat. Mus. Comp. Zool., jSTo. i. p. 64, fig. 4, 1865. 



Bahia ; 7 to 20 fathoms. 



