372 Mr. H. J. Carter on Specimens 



Discodermia sinuosa, n. sp. 

 (PL XVIII. fig. 1, a-h.) 



Surface even, discophorous ; disks (fig. 1, a) at first simple, 

 in juxtaposition, peltate, then foliate, with shallow denticu- 

 late margin (fig. 1, ^) ; afterwards more deeply notched and 

 foreshadowing a trifid division, with a tendency in some of 

 the notches to assume a circular form (fig. 1, c) ; then the 

 same more intensified and larger, when, overlapping each 

 other in situ, the circular notches become converted into aper- 

 tures, and then more especially present the sinuous lines wliich 

 characterize the species (fig. 1, d) ; finally transmuted into 

 branches which, becoming subdivided towards the extremities, 

 end in filigree expansions (fig. 1, e), which, in the deeper and 

 fully-developed structure, interlock with their neighbours by 

 subround tubercles constricted at the neck, which thus form 

 a grape-like mass (fig. 1,/'). Disk at the commencement or 

 when first recognizable simple, subcircular, with even margin 

 and short, central, smooth-pointed shaft projecting inwards, 

 nail-like, from the lower surface, and encircled above by faint, 

 broken, concentric lines, about 1 -300th inch in diameter 

 (fig. 1, a). Flesh-spicule minute, fusiform, somewhat inflated 

 in the centre, microspined and slightly curved (fig. 1, ^, A), 

 abundant throughout, but especially over the discophorous or 

 external layers. Size of largest specimen, which is consider- 

 ably worn and has been deprived of its disks, about half an 

 inch in diameter each way ; that of the smallest, which is 

 thin and spreading, hardly more than the discophorous or 

 outer layers thick. 



Hab. Marine. On Melobesian nodules. 



Loc. Gulf oi Manaar ; Basse Rocks. 



Obs. The circular notches of the disks separately, and the 

 sinuous lines which they present when overlapping each other 

 in situ, are almost identical with what is seen in Kaliapsis 

 cidaris ; but the absence of papillary projections on the sur- 

 face in the former at once points out the difference. 



Discodermia sceptrellifera, n. sp. 

 (PL XVIII. fig. 2, a-h.) 



Surface even, discophorous. Colour yellow, becoming 

 reddish brown under the influence of nitric acid. Disk simple, 

 circular, with even margin, presenting faint, irregular, con- 

 centric lines ; provided with a short, sharp-pointed, smooth 

 shaft, projecting inwards, nail -like, from its under surface 

 (fig. 2, a) ; soon becoming irregular in its outline (fig. 2, b) , 

 which assumes a trifid division (fig. 2, c), still more developed 



