A MONOGRAPH OF THE AUSTRALIAN SPONGES. 



By R. von Lendexfeld, Ph.D. 



Part VI. 



THE GENUS EUSPONGIA. 



II.-SUB-FAMILIA SPONGIN.E. 



Spongidfe of a massive bulbous or irregularly digitate or thick 

 lamellar shape. Vestibule spaces are developed in a few species 

 only, and where they are present they ai'e reciproc to those 

 of the AuleninsB, inasmuch as only inhalent poi-es are found in 

 their walls, whereas in the Auleninas, either inhalent and exhalent 

 pores, Oscula ai-e found in them, or there is a tendency towards 

 converting them into Oscula tubes, by the apertures of the exhalent 

 canals becoming more numerous in the walls of these spaces than 

 in other parts of the sponge surface. In those species of Sponginte, 

 which possess them at all, they are connected with the inhalent 

 canal system only. Such vestibule spaces have been observed in 

 Euspongia canaliculata and irregularis, and also in Hippospongia 

 and some species of Cacospongia. 



The skeleton is composed of "main" and "connecting" fibres. 

 The main fibres are disposed in a radial direction and slightly 

 branched in a pencillate manner. They are 2-12 times as thick as 

 the connecting fibres and generally cored with foreign bodies 

 sand-grains, &c. The connecting fibres are always free from 

 foreign bodies with the exception of Euspongia silicata. They are 



