300 



DISCOVERY REPORTS 



scarcely one-third of the disk radius. The scales of the ventral interradii of the same size 

 as those of the dorsal side of disk, rather thick. Buccal shields spade-shaped, with 

 rounded corners and a small rounded outer lobe. Adoral plates narrow, joining within, 

 with a conspicuous outer lobe separating the first lateral plate from the buccal shield. 

 Mouth papillae as usual in Ophionereis. First ventral plate squarish, but broader dis- 

 tally. The following ventral plates broadly contiguous, about as broad as long, with 

 convex outer edge and sides with a re-entrant curve. The outer corners not much pro- 

 duced. Dorsal arm plates rather squarish, with sides and distal edge almost straight. 



Fig. 29. ophionereis novae-zelandiae, n.sp. Part of oral side {a) and dorsal side {b). 

 Arm joints from middle of arm of a larger specimen; dorsal side (c). X20. 



22-5. 



The supplementary plate fairly large and distinct, almost rectangular in the proximal 

 part of the arm. Three slender arm spines, about the length of an arm joint. One large, 

 oval tentacle scale. Colour of dried specimen whitish, with a faint indication of brownish 

 bands on the arms. 



This species is about intermediate between Ophionereis porrecta, Lyman, and O. 

 aiistraUs (H. L. Clark). From the former it differs notably in the shape of both dorsal 

 and ventral arm plates. The arm spines also are longer and more slender than in O. 

 porrecta, and the colour is lighter. From the South African O. aiistralis it differs in the 

 disk scales being smaller and more uniform ; the shape of the dorsal plates and the 

 supplementary plates is also rather different (cf. Mortensen, Echinoderms of South 



