180 CEYLON PEARL OYSTER REPORT. 



Bubaris eruca (CARTER). 



1880, Hymerhaphia eruca, CARTER (4); 1894, Rhabderemia eruca, TOPSENT (59). 



There are three specimens of this very curious encrusting sponge in the collection ; 

 it has been well described and figured by CARTER (loc. cit.), who himself pointed out 

 its close resemblance to BOWERBANK'S Hymeraphia vermiculata, which is the type 

 species of the genus Bubaris. 



TOPSENT (62) has recently proposed to include this species in his genus Monocre- 

 pidium, distinguished from Bubaris by the tuberculation of the diactinal megascleres. 

 In Bubaris eruca the spicules in question are annulated rather than tuberculated. 



K.N. 183 (Stat. XLIII, off Kaltura, February 19, 1902, depth 22 fathoms) ; 239A, 

 240A (both from deep water off Galle and onwards up West Coast). 



Rhabderemia, TOPSENT. 



Encrusting or massive Ectyoninee in which the principal megascleres are styli with 

 strongly curved base, shaped like a hockey stick, and the principal microscleres 

 are contorted sigmata. There are no chelae and the echinating spicules appear 

 to be greatly reduced or absent. 



TOPSENT (48) established this genus in 1892, originally for the reception of CARTER'S 

 Microciona pusilla and M. intexta (57), and a new species described by himself under 

 the name Rhabderemia guernei. R. pusilla, being mentioned first, may be taken as 

 the type of the genus. R. guernei and the new species which I am about to describe 

 under the name Rhabderemia indica, agree so closely with R. pusilla that there can 

 be no reasonable doubt of their generic identity. R. intexta differs more from the 

 typical species, but may still, I think, be included in the genus. It is distinguished 

 from the others by the possession of spined megascleres and the absence of small 

 slender styli. There is in Mr. CARTER'S cabinet, however, a preparation labelled by 

 him " Microciona minutula," which is intermediate in spiculation, having large bent 

 styli minutely spined at the apex and also very slender styli slightly roughened at 

 the base. It is further characterized by having toxa amongst the microscleres, and 

 is evidently quite distinct from Rhabderemia (Microciona) pusilla, with which 

 Mr. CARTER has apparently confounded it.* 



It is probable that some other species hitherto referred to the genus Microciona 

 will also have to be included under Rhabderemia ; on the other hand, as I have shown 

 in dealing with Bubaris eruca, this species has been erroneously included in the genus 

 Rhabderemia by TOPSENT. 



Rhabderemia indica, n. sp. Plate XII., fig. 10. 



The specimen encrusts and almost completely envelopes some large fragments of 

 shell, and attains on one side of the shell a thickness of 7 or 8 millims. The shape 

 of the entire specimen with its enclosed shell-fragments is massive and irregular. 



* The name pusilla was intended by CARTER to be minutula, -vide CARTER (57 and 4). 



