"Vertical section of a fresh-water sponge (Spongilla), showing the arrangement of the canal-system. C, ciliated chambers; DP, dermal pores; Ex, excurrent canals; GO, openings of the excurrent canals; PG, paragastric cavity; SD, subdermal cavities; O, osculum." -Parker, 1900

Spongilla

"Vertical section of a fresh-water sponge (Spongilla), showing the arrangement of the canal-system.…