120 PROF. P. M. Duncan's beyision op the 



Interradia with a linear groove in the median line, broad above 

 the ambitus, narrow at the peristome, wath two principal vertical 

 rows of primary tubercles resembling those of the ambulacra in 

 structure, but larger, diminishing, however, in size actinally and 

 dorsally. There are also two rows of smaller primaries, smallest 

 actinally, which reach some distance above the ambitus, with 

 small secondary tubercles and granules irregularly distributed. 



Peristome small, pentagonal, with moderately large branchial 

 incisions. 



Spines various, but moderate in length, stout, tapering, sharp, 

 solid, finely striated longitudinally; a prominent milled ring. 

 Ophiocephalous pedicellarise abundant, large, their jaw-processes 

 much dentate ; gemmiform pedicell arise probably absent ; tridac- 

 tyle pedicellarise abundant. 



Fossil. Tertiary : Java ? 



Becent. Mauritius, Java, Samoa. 



Genus Pabasalenia, A. Agassiz, 1863, Bull. Mas. Gomp. Zool. 

 vol. i. p. 22 ; 1873, Revision, p. 435. Stewart, 1880, Journ. 

 Moyal Micr. Soc. vol. iii. p. 910. 



Test moderate in size, stout, elliptical, tumid, unsym metrical, 

 the long axis passes through ambulacrum I. and interradium 3, 

 and is oblique to the antero-posterior axis. 



Apical system large, prominent. Basal plates large. Periproct 

 small, with four triangular plates ; anus at their inner points. 



Ambulacra with two vertical rows o£ plain primary tubercles, 

 not reaching the apical system ; pairs of pores in arcs of three 

 pairs. 



Interradia with a small number of coronal plates, carrying two 

 vertical rows of plain primary tubercles resembling those of the 

 ambulacra. 



Peristome large ; branchial incisions slightly raised ; buccal 

 plates with spinules. Jaws with a high foramen ; teeth keeled. 

 Spines stout, cylindrical, pointed, moderately long. 



Pedicellarige few, the gemmiform without a secondary solid 

 fang. Tridactyle pedicellariae delicate. 



Becent. Zanzibar, Kingsmill Islands, Benin Islands. 



