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K, MITSUKUllI : STUDIES ON 



Description : — " ]jody indistinctly pentangular. Pedicels numer- 

 ous, cylindrical, long, forming apparently a double row along 

 each ambulacrum ; at the middle of the body they seem to be more 

 crowded, there being three to four rows, but tiiis is probably a 

 result of the contracted state of the body. Tentacles ten, two 

 ventral smaller. Anus with small teeth. Pohan vesicle and 

 madreporic canal single. Calcareous ring very fragile, the inter- 

 radial pieces being conical, pointed anteriorly ; the radial obtuse, 

 furrowed anteriorly and terminating posteriorly in two very slender 

 prolongations. Deposits crowded, of two kinds ; in the external 

 layer of the perisome small reticulated spheres or globular cups; 

 in the internal layer numerous hollow fenestrated ellipses of 

 different sizes and shapes, some being of a more elongated form, 

 otliers more rounded, globular, and some being several times 

 larger than the rest ; among the larger ellipses are found here 

 and there rather large scale-like bodies, composed apparently of 

 a network of several superposed layers. Undeveloped ellipses, 

 consisting of a small oval concave plate with four holes, may 

 also be found. The pedicels have, round the large terminal 

 plate, some irregular perforated plates, and, besides, numerous 

 elongated rods with four holes at the slightly enlarged middle, and 

 a row of holes along each arm ; the middle of the rods usually 

 carries a kind of low conical, rounded spire. Length of the 

 largest specimen, 55 mm. Colour whitish." (Thkel). 



