EEPORT ON THE OPH1UROIDEA. 21 



Ophiozona. 

 Ophiozona, Lym., 111. Cat. Mus. Comp. Zool., No. 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 papillae. Numerous even, close-set mouth papillae. 

 Side mouth shields wide, and nearly or cpute 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 plate is thick and swollen; sometimes single, and some- 

 times divided in two. Of the discoid arm bones, 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 of Ophiozona. 



, , c Arm spines nearly as long as side arm plates : lowest one \ --, i ■ 

 4-5 arm spines. , jo r i Ophiozona imjn-essa. 



Small separated 1 longest .) 



a 1 ' ' L Ann spines equal and very short, .... Ophiozona pacifica. 



j-Radial shields large and touching, . . . Ophiozona nicea. 



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



tentacle pores only, .... 



3 arm spines, . S Lar S e radial shielcls ' bearin °' a blunt s P ine on their outer i Ophiozona temOata. 



( end, . . . . . . .J 



r Radial shields small and separated, . . . Ophiozona stellata. 



Large pointed radial shields nearly touching at their middle ) 



. . > Ophiozona antrflarum. 



point, . . . . . . J *■ 



ies > • \ Large, oval, well separated radial shielcls, . . . Ophiozona depressa. 



Radial shields wide and touching. First side arm plates \ 



very wide, and extending into centre of interbrachial y Ophiozona (?) dvbia, 

 space, . . . . . . J 



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



Ophiohpis impjressa, Ltk., Addit. ad Hist., part 2, p. 101, pi. ii. fig. 3, 1S59. 

 Ophiozona impressa, Lym., El. Cat. Mus. Comp. Zool., No. i. p. 64, fig. 4, 1865. 



Bahia ; 7 to 20 fathoms. 



o 



3 ) 



> Ophiozona insularia. 



a 



GO 



o 



a 



a 

 O 



