APLYSINOPSIS. — LUi'l'ARlA. 151 



mostly cut transversely iu radial longitudinal sections. The final ramitioations 

 of the inhalant canal-system are remarl^ably slender, only 0-02 millim. wide ; 

 they open by large, generally very conspicuous mouths, 0-01 millim. wide, into 

 the slightly irregularly spherical ciliated chambers. The latter are 0-036 millim. 

 wide, and destitute of special efferents. The final ramifications of the exhalant 

 system are much wider than those of the inhalant system : the narrowest over 

 0*4 millim. wide ; always wider than the chambers. 



The ground-substance in the vicinity of the ciliated chambers is very granular 

 and opaque. 



Embryos in various stages of development have been observed in some 

 specimens of this species. They do not appear confined to any particular 

 region, but seem to be scattered throughout the whole of the sponge. 



GEOCiRApniCAL Distribution. — North coast of Australia: Torres Straits 

 {Maclcay). East coast of Australia : Port Jackson, N. S. W. (Leadeufeld). 



Genus LUFFARIA. 



Spongidse with a skeleton composed of thick -walled pithed 

 fibres, which are distinguished into longitudinal main fibres, stout 

 reticulating primary connecting-fibres, and slender secondary con- 

 necting-fibres ; the latter form a fine netwoik in the polygonal 

 meshes of the primaries. 



Luffaria variabilis, Polejaeff. 



Luffaria varlahilis, N. de Polejaetf, lieport on the Keratosa. — Eeports on the 

 Scientific Results of the Voyage of H.M.S. ' Challenger,' Zoology, vol. xi. 

 p. 69 (1884). 



Massive, lobose, or slender digitate sponges. The digitate forms are ramified ; 

 the cylindrical branches straight and pretty uniformly 8-12 millim. thick. 

 They attain a length of 250 millim. and are distally rounded. The massive 

 lobose forms are horizontally expanded, attached by a narrow base, and attain 

 a height of only about 50 millim. In the digitate forms the cylindrical 

 branches grow out from a small basal mass. 



The surface is covered with small, sharp, and slender conuli, 1"2 -Tiillim. 

 high, which are extended below. The conuli are about 2*5 millim. apart. The 

 oscula are circular or oval, 2-3 millim. wide, and rather scarce ; they are 

 scattered irregularly over the surface. No oscula are found on the summits 

 of the digitate processes. Aconulous patches are figured by PolcjaeS on the 

 surface of the massive form. 



