46 K. Ml'ISTTKURT AND S. IKEDA. 



the same direction as itself. The surface between the two cutting 

 edges was deeply concave ov V-shaped ; the angle at the tip of rostrum 

 was about 45°. Beyond the notch at the base of the cutting edge, there 

 was on the anterior edge of the alrr, a low broad tooth with a sharp 

 point at the end further from the notch. Beyond the tooth, the 

 anterior edge of the alec was even, the lamina of the rostrum was 

 short and strongly emarginate in the median line. The rosfrion was 

 dark brown in colour, deepening into black towards the tip ; the al<T, 

 were faintly Ijrown. The f/ular lamina were folded in two at the 

 median line producing a quaduilateral plate on each side ; they were 

 dark brown along the median folding ridge, while the lateral quadri- 

 lateral plate was tolerably dark brown with colourless margins. The 

 Measurement, were as follows (see Fig. ()h) : — a, — d j)iecliaUj/=14 mm., 

 a—f mcdialhi—2D mm., a — h — 10 mm., a—e — fi7 mm., a—c=80 mm., 

 d — c — 3C) mm., q — ]t~14 mm., a — h — IS mm., breadth of tlic tooth g = 

 ii-j mm., hrcadtli at tltr iiotcli h — S mm., breadth at the tooth ri=^12 mm., 

 breadth at h — HO mm. 



The Bciduki was like those of the Decapoda in general. Fig. Sa, 

 gives a row of teeth from the part of the ri))bon near the mouth open- 

 ing, and Fig. 56 the same from a more posterior part. Breadth of the 

 rib])on was about 5 mm. 



The Internal Shet,l (Fig. '2) had been slightly injured by 

 the spear wound in the middle of the dorsal surface. The posterior half 

 had also been taken out by some pei-son who examined it before us but 

 was carefully preserved. The anterior half we took out ourselves. We 

 found out that we could easily put the pieces together and make out the 

 shape of the whole. The .^hell was very thin, quite translucent, and 

 lanceolate in shape. Its Jeiuith iraa (14 cm. Its greatest breadth 

 (between LS-30 em. from the anterior liroader end) icas 7 em. and 

 topered fi-om this zone to ])oth ends. As the anterior end (uppermost 

 in the figure) is quite near the broadest zojie, the shell ends with rather 

 a blunt broad point at that end." Posteriously it tapered very gradually. 

 The mid-rib was most distinct at the posterior end, becanie lower, 



