12 SPONGES. 
Fic. 11.—Ascetta primordialis. 1, ov, exhalent opening ; /, inhalent pores ; 
&, ova, Star-like spicules are seen on the outside. II. Section showing 
pores (2), with cilia of the cells extending into them. III. Cell show- 
ing lash, or cilium. IV. Same, with lash retracted. V. Embryo of 4s- 
cetta mirabilis, VI. Section of embryo. 
