ACTINOrODOUS HOLOTHUEIOIDEA. 



85 



on the anterior part of the dorsum have the most eonspicuous 

 "svarts. 



The calcareous bodies are tables and buttons. Tables 

 (textfig. 17 a, h) are large and very thickly spread on the surface 

 of the body. On examin- 

 ing with a hand-lens, the 

 spires of the tables may 

 be recognized as minute, 

 thickly-set spines sticking 

 out from the surface of 

 the body. The basal disk 



^ Textfig. 17. 



has a smooth margm and 



^ iLolothur'ui imitntwns : a, h — 



is almost always 0.1 mm. Tables; <•— Button. (<y/.x270.) 



in diameter and somewhat rectangular with rounded corners. 

 It has eight large holes in the periphery and one larger 

 central hole. Over the central hole rises the spire with four 

 columns. It is about 0.08 mm. in heiglit, and tapers gradually 

 upward. It has mostly two crossbeams besides the coronal 

 connection. Over ten teeth project not only from the crown 

 but also from the columns at the level of the crossbeams. Tables 

 with one crossbeam are also frequently met with in some 

 specimens. Buttons (c) are regular, almost always with three 

 pairs of holes. The margin is smooth and somewhat crenate. 

 ►Supporting rods in the ambulaeral appendages have expansions 

 in the middle and at the two ends. 



In the Sakibaru specimen wdiicli was opened, two long 

 Polian vesicles were found, one 3.8 cm. and the other 1.7 cm. 

 long. Stone-canal one, on the right side of the dorsal mesentery, 

 free, with an enlarged and elongated head. Sexual origans stiJI 

 small and immature. Cuvierian organ a bundle of about -!(), 



