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TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY 



the crumb-of-bread sponge (Halichondria panicea), shown 

 at 3, the spicules are of silica or flint. This enables us to 

 distinguish two important sets of sponges, the Calcareous 

 and the Siliceous. 



Sponges were at first thought to be lifeless, then for 

 a time they were regarded as plants. Professor Grant, 

 after whom a common sponge was called " Grrantia," first 



r-'p-y^-k'iQ 



^5©WI^§^f V 



Fig. II. 



showed that they were animals, and that while alive a 

 current of sea-water passes through the sponge — in by 

 minute pores all over the surface, and out by one or more 

 larger crater-like openings. 



The reports upon the sponges of our district have been 

 written bv Dr. R. Hanitsch. 



