Diagram showing the Ascon type of sponge. ec., ectoderm; r.c., radiating canals; i.p., internal pores; mes., mesenchyma, e.p., external pores.

Ascon Sponge

Diagram showing the Ascon type of sponge. ec., ectoderm; r.c., radiating canals; i.p., internal pores;…

"Diagrams to illustrate the development of one of the simpler types of sponge: I, the egg; 2, section of 16- to 32-celled stage; 3, section of later stage, a ciliated larva (blastula); 4, gastrula; 5, section through older larva which has become attached by the end containing the blastopore. New openings break through by the coalescence and perforation of the ectoderm and entoderm, and and a form results... a, archenteron; bl., blastopore; ec., ectoderm; en., entoderm; mes., mesenchyma; s, segmentation cavity." -Galloway, 1915

Simple Sponge Development

"Diagrams to illustrate the development of one of the simpler types of sponge: I, the egg; 2, section…

"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.…

"Transverse section through the wall of a cylinder (parallel with the course of the canals), showing one incurrent canal (IC), and one radial (R) throughout their length; sp, triradiate spicules; sp', oxeote spicules of dermal cortex (dc); sp'', tetraradiate spicules of gastral cortex (gc); ec, ectoderm; en, endoderm; pm, pore membrane; pp, prosopyles; ap, apopyle; di, diaphragm; exc, excurrent passage; PG, paragastric cavity; em, early embryo; em, late embryo. The arrows indicate the course of the water through the sponge." -Parker, 1900

Sycon Gelatinosum

"Transverse section through the wall of a cylinder (parallel with the course of the canals), showing…

Diagram showing the Sycon type of sponge. ec., ectoderm; r.c., radiating canals; i.p., internal pores; mes., mesenchyma, e.p., external pores; en1, entoderm; en2, flagellate entoderm; f.c., flagellate chambers.

Sycon Sponge

Diagram showing the Sycon type of sponge. ec., ectoderm; r.c., radiating canals; i.p., internal pores;…