216 eLATHBIODENBEOIf. — K ALYKENTEKON. 



Clathriodendron nigra, n. sp. 



The sponge consists of a mass of very slender branches arising from a small 

 base. These are somewhat compressed, and on an average 4 millim. thick. 

 The}^ ramify in an irregular dichotomous manner, and appear slightly thick- 

 ened at their distal ends. 



The skeleton consists of bundles of straight or slightly curved styli, which are 

 0-7 millim. long and 0-017 millim. thick. These fibres are disposed longitudi- 

 nally and transversely, and form a network with square meshes. They are 

 0'07 millim. thick, and the meshes 0'05 miUim. wide. Here and there these 

 fibres are also connected by single spicules, similar to those within the fibres. 

 There is hardly any horny substance visible. The fibres are echinated by styli 

 0-1 millim. long and 0-01 millim. thick, with very small spines. These are 

 comparatively very scarce, and stand singly at long intervals, projecting at an 

 angle of about 45 degrees from the spicule-bundles which form the fibre. 



Geographical Distribution. — East coast of Australia {Ramsay). 



Genus KALYKENTERON, nov. gen. 



Exceedingly hard and tough cup-shaped Desmacidonidse, with 

 a skeleton composed of very thick spicule-bundles which are 

 echinated by spined strongyla. 



Kalykenteron elegans, n. sp. 



A very elegant, conical, cup-shaped sponge attaining a height of 220 millim. 

 The margin of the cup is circular and has a diameter of 120 millim. Both 

 surfaces are very irregular and covered with numerous projections of varying 

 shape and size. The outer surface is somewhat rougher than the inner. The 

 small circular oscula are confined to the latter. 



The skeleton consists of a dense network of exceedingly thick fibres. The 

 main fibres, which extend longitudinally from the base to the margin of the 

 cup, are 0*2 millim. thick. The connecting trausverse fibres have an average 

 diameter of 0*07 millim. The meshes of the network are 0-48 millim. wide. 

 The fibres consist of dense masses of oxea which are all parallel and disposed 

 longitudinally. These oxea are curved in the middle, on an average 0*27 

 millim. long and 0-012 millim. thick, not very sharp, and rather abruptly 



