524 A MONOGRAPH OF THE AUSLRALIAN SPONGES, 



In the surface there is a very dense and irregular network 

 which does not resemble the network of the interior at all. This 

 is similar to the skeleton of Euspongia officinalis and to the 

 interior of the skeleton of the species of the genus Densalis. 



73. SPECIES. EUSPONGIA REPENS. Von Lendenfekl. 



DiTELA REPENS. Solenka. (1) 



Selenka did not describe this species very minutely, but his 

 excellent figure makes it sufficiently certain that the sponge to be 

 described below, and Selenka's Ditela repens are identical. 



SHAfE AND Size. 



In outer appearance this sponge, particularly the skeleton of it, 

 resembles some forms of chalinid sponges very closely, and it 

 forms also in other respects a transition form between my sub- 

 families Sponginfe and Chalinospinae. It is digitate, creeping and 

 irregular. The digitate parts coalesce occasionally to form a 

 lamellose extension, usually however they only grow together in a 

 few places where they touch, They attain a length of 100 mm., 

 are cylindrical, terminally rounded, and from 12-20 mm. in 

 diameter. There thickness is generally very uniform throughout. 

 My specimens are more regular than the one depicted by Selenka. 



Surface. 



The surface of the skeleton, and also of the animal, is slightly 

 conulated. The conuli are small and low, on an average, 1 mm. 

 apart and 0*4 mm. high. They are disposed very regularly, N^o 

 sand is found in the skin, which is strongly protected by the 

 dense Ditela network of fibres in it. 



The oscula measure from 2-4 mm., are circular and occasionally 

 veiy slightly raised over the surface. They are situated terminally, 

 but also occur on the surface, particularly of large and irregular 

 digitate pieces in great numbers. 



(1) E. Selenka. Ueber einige neue Schwammme aus der Siidsee. Zeit 

 schrift fur wissenschaftliche Zoologie. Band 17, Heft 4, 1867, p. 567. 



