70 VERRILL, SYNOPSIS OF 



the published figures are iusufficient to determine satis- 

 factorily. 



DiscosTOMA Ehrenberg, 1834. 



Discosoma Leuck. (uou Discosomus Oken, 1816 ; nee Discosoma 

 Perty, 1830). 



Discosoma (^pars) Edw. and Haime, CoralL, I, p. 255. 



Column low, smooth, smaller than the disk and base. 

 Disk very broad, covered with numerous rounded ver- 

 rucas or tabercles, which are arranged in regular radiating 

 lines, apparently a single series in each line, each line 

 corresponding to the top of a single internal chamber. 

 Tentacles not distinct from the tubercles of the disk. 

 Type, D. nummiforme Leuck. 



DiscosTOMA ruNGiFORME Vcrrill, sp. nov. 



Plate 1, figure 7. 



Base thin, broadly expanded, nearly as large as the 

 disk. Column much narrower, low, smallest in the mid- 

 dle, expanding rapidly to the margin of the broad expla- 

 nate disk, which has a thin, regularly scalloped and slightly 

 undulated edge. The central region of the disk is sunken, 

 and from the depression arises a cone, having the small 

 sub-circular mouth at its summit. The mouth has a nar- 

 row, revolute border, which is marked by many slight 

 sulcations. The entire disk, including the surface of the 

 cone even to the lips, is closely covered by an immense 

 number of small rounded tubercles, which are subequal 

 and arranged in many narrow radiating series, between 

 which the internal lamellae may be seen through the disk- 

 membrane, as narrow, dark, radiating lines. The tuber- 

 cles are mostly closely crowded in a single row in each 

 series, but in some cases are so crowded as to form two 

 •alternating rows. Breadth of disk, in alcohol, .8 of an 

 inch; height .3 of an inch. 



The above description has been prepared from speci- 

 mens preserved in alcohol. The disk and tentacles do 

 not appear capable of contracting. Young specimens. 



