ACTIXOrODOUS IIOLOTHUKIOinEA. 



49 



Description : — Tentacles 20. Papillae oii the dovsal surface ; 

 pedicels on the ventral surface, both numerous. Calcareous deposits 

 alike in the dorsal and the ventral perisome. The outer layer 

 consists of roljust, rather sparsely scattered tables with a smooth 

 disk O.OG — 0.08 mm. in diameter, and a spire termiiiathig in 10 — 

 20 teeth. The thick lower layer consists of closely packed, hol- 

 lo^y, fenestrated ellipsoids, 0.07 mm. long, and with four rows of four 

 openings each, sometimes with a central axis-like rod piercing 

 through the middle. Color plain black, or having on a coal-black 

 ground 5 — 7 snow-white transverse spots on the sides and a circle 

 of smaller white spots on the dorsum. There exist all intermediate 

 sliades of coloration between these two extremes. Calcareous ring 

 conically narrowed in posterior direction. Tnterradialia about half 

 as high as radialia, wliich are three-pointe<l. Cuvieriaii organs in 

 bundles of 5 — 10, at the base of right re.'^[)iratory tree. Ten- 

 tacular ampullae very large. 



liemai'ks : — The tables (textdg. 10, / — n) arc quite stout, with 

 a more or less complete circle of holes around the large central 

 one. <^nly one cross-beam. The spire ends in a number of 

 teeth, (^f the ellipsoids, Selenka says (loc. cit.) that they arc 

 "zusammengedriickten liolilen, von viermal vioi- Lochern durch- 

 bolirten Kalkellipsoiden von 0.07 mm. Tiange, zuweilcii von einem 



