140 ART. 2. H. MATSUMOTO : 



almost similar to those of the preceding, but the radial shields are 

 more massive and the inner parts of the genital plates, as well as 

 the genital scales, are thin and plate- like. 



According to Lyman's statements, the internal structures of 

 Hemieuryale pustulata von Maeïens, 1867 are essentially similar 

 to those of Ophiochondriis, but more specialised. The genital plate 

 and scale of the same side of a radius are also soldered together. 

 The peristomial plates are simple and comparatively small. The 

 articular shoulder of each vertebra is very stout, while the articular 

 peg is entirely absent. 



Key to Japanese species of OpJiiomœris, 



^~T>isk entirely free of large, spherical tubercles ; each radial pair of 

 radial shields separated from each other b}- a row of two or three 



plates ohslricta 



AA — Large, spherical tubercles present along the outer margins of the 

 radiais and along the adradial borders of the radial shields; radial 

 shields joined in pairs along the whole length prqjecta 



Ophiomœris obstricta (Ly^fan), 



Ophioceramis{?) obstricta: Lyman, Bull. Mus. Comp. ZooL, V. 1878, p. 

 124, PI. VI, figs. 164-166 ; Lyman, Rep. Challenger, V, 1882, p. 26, PL XI, 

 figs. 1-3. 



OpMomœns obstricta : Kœhler, Kxp. Siboga, XLV, Pt. 1, 1904, p. 17. 

 Ophinrases obstr ictus : Clark, Bull. U. B. Nat. Mus., LXXV, 1911, p. 

 250, fig, 122. 



Eastern Sea ; 95-135 fathoms (Clark). 



Lat. 5^ 42' S., long. 132° 25' E.; 12i) fathoms (Lyman). 



