4 PLATE II. 



spiculum from the ciliary fringe of the mouth of the 

 cloaca. X 80 linear. 



Fig. 10. An acerate spiculum, from the defensive 

 cone of the inhalent system. X 80 linear. 



Fig. 11. One of the large fusiformi-acerate spicula 

 supporting the base of the ciliary fringe of the mouth 

 of the cloaca. X 80 linear. 



Fig. 12. A rectangulated triradiate spiculum, from 

 near the base of the ciliary fringe of the mouth of the 

 cloaca. X 80 linear. 



Fig. 13.- -A spiculated, rectangulated, triradiate, 

 defensive spiculum from the base of the ciliary fringe 

 of the cloaca. X 80 linear. 



Fig. 14. An equiangular triradiate spiculum of the 

 skeleton. X 80 linear. 



Fig. 15. A spiculated, equiangular, triradiate, de- 

 fensive spiculum from the interior surface of the 

 cloaca. X 80 linear. 



GRANTIA ENSATA, Boiverbank. 



Vol. ii, p. 25, ' Mon. Brit. Spongiadse.' 



Fig. 16. Representations of three specimens of 

 G. ensata. Natural size. 



Fig. 17. Two young specimens of the same species 

 based on a fragment of shell. Natural size. 



Fig. 18. A portion of the surface of one of the 

 specimens of G. ensata exhibiting the mode of disposi- 

 tion in the direction of the long axis of the sponge, of 

 the large fusiformi-acerate defensive spicula. X 50 

 linear. 



Fig. 19. One of the spiculated, equiangular, trira- 

 diate internal, defensive spicula from the cloaca of 

 G. ensata, the spicular ray being very long and ensiform. 

 X 80 linear. 



Fig. 20. Represents one of the equiangular trira- 

 diate skeleton spicula of G. ensata. X 80 linear. 



