164 BRITISH SPONGES: 



4. SPONGIA, Liniiffius. 



Spongiae pars, Lin. Lam. Lamour. Achilleum, Schweig. Beo- 



bacht. vii. Haiidh. 421 Spongia, Flem. Brit. Anim. 524. 



Blainv. Man. 529. 



Character. Body multiform^ very porous^ elastic, 

 composed of a network of corneous fibres inosculating in 

 every direction and traversed by tortuous canals opening on 

 the surface by wider orifices ; the fibres often contain im- 

 bedded spicula : gelatine fugacious : marine. 



Ohs. " In the horny species of Porifera," says Professor 

 Grant, " the skeleton consists of thin elastic tubular translu- 

 cent filaments united together and distributed around the pores, 

 canals and vents. These horny, tough, flexible threads have a 

 close analogy in their mode of distribution through the whole 

 interior of the body to the tough connecting matter of the spi- 

 cula in the earthy species, and they give form and support to 

 the whole fabric. Sometimes the internal canal which extends 

 through these tubular horny filaments is filled with an opake 

 matter which gives a greater friability to the threads ; but most 

 frequently they contain only a transparent coloui'less fluid." 

 Outlines of Comp. Anatomy, p. 8. 



