﻿SPONGES— HALLMANN. 26" 



stouter-spiculed specimens, but in any case they are scarce 

 and in the first-mentioned two specimens have not been 

 observed. 



(ii.) The auxiliary tylostyli are normally straight, but in 

 some specimens a considerable proportion, perhaps even a 

 majority, are variously flexed. They range in length from less 

 than 160 to (usually) slightly more than 300^1; their greatest 

 observed length in any specimen was 350 i^. 



I have quoted Antherochalina teniiispi^ia, Lendenfeld, as a 

 probable synonym of O. tenuis on the evidence of a small 

 piece of a British Museum specimen labelled with the name 

 and locality {viz., Western Port, Victoria) of Lendenfeld's 

 species. As the fragment conforms in external features with 

 Lendenfeld's description, I have but little doubt that the name 

 attached to it is the correct one, and would say, therefore, that 

 in respect of its spicular characters A. tenui spina has been 

 wrongly described. 



In some features of the skeleton O. tenuis resembles 

 ClatJiria (?) chartacea, Whitelegge {vide p. 208) — a species 

 from which, externally, it appears to be indistinguishable. 



Locs. — Port Philip, 1S-20 fms. {Carter; Dendy ; Austr. 

 Mus. Coll.); forty miles west of Kingston, South Australia, 

 30 fms. ("Endeavour"). 



Ophlitaspongia inornata, sp. nov. 

 (Plate xxxvi., fig. 2, and fig. 57.) 



Sponge stipitate, ramose; branches short and crooked, 

 mostly confined to one plane, sometimes anastomosing. 

 No apparent dermal membrane. Oscula doubtfully 

 present. Skeleton: In the older parts of the sponge, the 

 axial region of the branches is occupied by a dense plexus 

 of stout, generally aspicidous, horny fibres, by a pro- 

 fusion of longitudinally-disposed extrafibral spicules 

 {principal styli) arranged in loose bundles and strands, 

 and by single spicules ivhich, though generally scattered 

 ivithout order, appear in places as if arranged, retictdately. 

 From the axial region there run outivards and upwards 

 to the surface, fibres with diver gingly disposed and fre- 

 quently echinating spicules which, at the- extremity of the 

 fibre, form a projecting tuft; these fdires are foined by 

 transverse and inter reticulating paucispicidar connecting 

 fibres forming with them rectangular and polygonal 



