88 ART. 2. — H. MATSÜMOTO 



Sagami Sea (Döderlein). 



Astrotoma sobrina Matsümoto, 



Astrotoma murrayi : Döderlein (non Lyman, 1879), Abb. Matli.-Phys. 



Kl. K. Bayer. Akad. Wiss., Suppl.-Bd. I, 1911, p. 23, fig. 1, PI. VI, figs. 



1 & la, PI. VII, figs. 14-146. 



Five specimens ; off Misaki, Sagami Sea. 



Diameter of disk 34 mm. Length of arms 200 mm. Width 



erf arms at base 7 mm. 



Disk five-lobed, flat, rather sunken towards the centre, covered 



with very fine, smooth, closely soldered granules and many small, 



oval plates, which are sunken below the level of the granules ; 



there are also on the disk numerous, large, smooth, spherical or 



^ghtly cylindrical tubercles with rounded ends. Radial ribs 



almost indistinguishable. Inter- 

 brachial ventral surface covered 

 by a thick, leather-like skin, 

 which becomes gi-anulated on 

 drying. Genital slits rather large 

 and divergent. The madreporic 

 shield is small, but very distinct, 

 more or less oval, vertical, lying 

 at the inner corner of one of the 

 interbrachial ventral surfaces. 

 The area inside the ventral 

 interbrachial surfaces, as well 

 as the brachial spaces, are 

 covered with thick, irregular, 

 pavement-hke plates and smooth, 

 scattered tubercles, which are 



F*ig. 26. Astrotomn sohrlnn. <i. Froni above. 

 x|. h. From below. xl|. c. Side vieM- 

 of three arm joints near disk, x 3. 



