photo B. Picton
photo B. Picton
photo T. Crabtree
from Sponge V
from Sponge V
Hoeksema's photos of raisin-casts of galleries in Ostrea
drawings of habits and papillae of Topsent, 1888a
Bowerbank's (1874) drawing of massive form
Sponge V drawing of spicules by C. Morrow
showing internal damage