PAPILLINA. 59 



the margins of lamellar individuals or in groups on the massive ones ; they 

 are circular and have a diameter of 8 millim. ; the oscular tubes which extend 

 down from them are much curved, have a circular transverse section, and 

 do not anastomose. The depressions between the papillao are occupied 

 by perforated membranes ; the inhalant pore-sieve appears accordingly as a 

 continuous network of broad zones. In these a reticulation of 0-2-0*4 millim. 

 wide bands, the meshes of which are 0*4-0'7 millim. wide, is observed ; the 

 mesbes are again subdivided by slender bands into three to six parts, in each 

 of which there are on an average eight 0"0o millim. wide pores. Large canals, 

 0-8 millim. in diameter, are found in abundance below this region ; 5 millim. 

 below the surface they join and open into tangential canals, of irregular 

 transverse section, which have an average diameter of 2-5 millim. ; from these 

 canals the smaller inhalants originate, which form anastomoses ; the exhalant 

 canals are irregular and wide, Uke the inhalants, and join to form oscular 

 canals 0'2 millim. in diameter, which open into large tubes. 



Skeleton. — The skeleton consists of supporting spicules and microsclera. 

 The Megasclera form irregular, on an average 0*6 millim. thick bundles ; they are 

 tylostyli, measuring 0*8 x 0-018 millim., obtusely pointed at one end, and gene- 

 rally slightly curved ; the bulb is situated terminally, spherical, and measures 

 0*023 millim. in diameter. The Microsclera are spined strongyla of varying 

 shape ; they measure on an average 0'06 x 0-01 millim. ; are either straight or 

 curved, and covered with irregularly scattered, conic spines, which are 0-01 

 millim. long and generally at the base half as thick ; these spicules are very 

 abundant, particulai-ly in the canal-walls. 



GEOGEAPnicAL DiSTBiBUTioN. — East coast of Australia : Port Jackson, 

 N. S.W. {Lendenfeld). 



Papillina ramtJosa, n. sp. 



Massive, lobose, very irregular sponges, attaining 200 millim. in length, 160 

 in breadth, and SO in thickness. The surface is smooth, but rendered very 

 uneven and irregular by numerous digitate, lamellar, or tubercular excres- 

 cences ; these processes are generally developed more highly at the distal 

 ends of the lobes than on their sides ; the digitate ones all extend towards the 

 terminations of the lobes. Colour light purplish brown in spirit, the same colour 

 in the interior and on the surface. Small vertical inhalant canals join to form 

 stems 0"1 millim. wide, which open into tangential canals situated 0-6 millim, 

 below the surface. These rather scarce canals are irregular in shape and 

 measure on an average 0*3 millim. in diameter ; they represent the subdermal 

 cavity, which is not highly developed. The interior of the sponge is very 

 dense ; the canals are not numerous, and have an average width of only 0-12 



