74 CHONDKOSIA. — SPONGILLA. 



from those in Chondrosia reniformis. The exhalant canal-system is simple and 

 not lacunose ; it shows no peculiarities. 



Geogeaphical Disteibution. — East coast of Australia : Port Jackson, 

 N. S. W. {Ramsay). 



Chondrosia collectrix, n. sp. 



Irregular, incrusting sponges, which attain a height of 20 millim. and a 

 breadth of 00 millim. The surface is smooth or slightly conulated. The body 

 contains a great quantity of foreign material, portions of hydroid skeletons, 

 sand, &c. ; the sponge-tissue itself appears only as a cement between these 

 foreign bodies ; there are fewer in the outer layers than near the base of the 

 sponge. The surface of spirit-specimens is light purplish grey ; the interior 

 brown. Subdermal cavities are found in the shape of tangentially extended 

 canals 0*2 millim. below the surface, which are on an average 0*17 millim. 

 wide, and connected with the inhalant pores on the outer surface by straight 

 or curved canals, 0*024 millim. in diameter. The inhalant canals, which 

 extend from the subdermal cavities centripetally, are irregular and 0*4 millim. 

 wide. The interior is very dense. 



Geogeaphical Disteibution. — East coast of Australia : Port Jackson, 

 N. S. W. {Ramsay). 



4. Ordo COENACUSPONGI-E. 



Silicea with pretty soft mesoglcea and oval or spherical, not 

 very large, ciliated chambers. A supporting skeleton is always 

 present ; it is composed of diact, monaxon megasclera, held 

 together by a varying amount of spongin ; or of spongin-fibres 

 without proper siliceous spicules, in which foreign bodies are 

 often imbedded. Microsclera never stellate. 



FamiHa SPONGILLID^. 



Freshwater Cornacuspongise, with gemmulee and a skeleton 

 composed of spicule-bundles. 



Genus SPONGILLA. 



Spongillidae, the spicules in the gemmule-capsules of which are 

 spined oxea. 



