644 a monograph of the australian sponges, 



Canal System. 



The whole structure is excessively lacunose and light. The 

 wall of the cup is pervaded in every direction by wide and 

 anastomosing lacunae, which indicate that this species possesses 

 very highly developed vestibule cavities. No trace of oscula is 

 visible. 



Skeleton. 



The main fibres are straight, and here and there flattened and 

 perforated. They measure 0-07 mm. in thickness and are 1 mm. 

 apart. Their surface is rough and even slightly spiny. They are 

 cored with longitudinally disposed foreign siliceous spicules. 

 0"1 mm. on an average in length. 



The connecting fibres form a net-work, the meshes of which 

 average 0'2 mm. in width, the thickness of the connecting fibres i» 

 0'06 mm. on an average. The connecting fibres only contain very 

 few foreign spicules, much fewer than the connecting fibres of 

 silicata. 



Geographical Distribution. 

 East Coast of Australia. (Ramsay.) 



Bathymetrical Distribution. 

 Shallow water 1 



79. SPECIES EU-SPONGIA FOLIACEA. Ridley. 



EUSPONGIA FOLIACEA. Ridley (1). 

 ? SPONGIA FOLIACEA. Esper (2). 

 ? PLATYCHALINA FOLIACEA. Ehlers (3). 



(I) Stuart 0. Ridley. Spongida. Report on the Zoological Collections, 

 made in the Indo-Paoific Ocean during the Voyage of H.M.S. Alert, 18S1-2. 

 British Museum of Natural History, Catalogue 1884, p. 378. 



I:2)E. T. C. Enper. Die Pllanzenthiere. Theil J. Seite 201, 1791. 



(3) -E. Ehlers. Die Esperschen Spongien in der Zoologischen Sammlung 

 der K. Universitiit Erlangen Programm zum Eintritt in den Senat der 

 Koniglich Fridrich-Alexander Universitiit in Erlangen. Erlangen 1870. 

 Seite 21. 



