ClipArt ETC
"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…

The sponge, a many celled animal, begins its life as a single-cell, the egg. First division in into two cell stage.

Sponge Develoment

The sponge, a many celled animal, begins its life as a single-cell, the egg. First division in into…

The sponge, a many celled animal, begins its life as a single-cell, the egg. Second division into the four cell stage.

Sponge Develoment

The sponge, a many celled animal, begins its life as a single-cell, the egg. Second division into the…

The sponge, a many celled animal, begins its life as a single-cell, the egg. Fourth division into a sixteen cell stage. This repeated process give the young sponge the general form of Pandorina.

Sponge Develoment

The sponge, a many celled animal, begins its life as a single-cell, the egg. Fourth division into a…

The sponge, a many celled animal, begins its life as a single-cell, the egg. The continued division of its cells result in the formation of a hollow globe of cells called the blastula, similar to Volvox, and at this point the young larva leaves the parent.

Sponge Develoment

The sponge, a many celled animal, begins its life as a single-cell, the egg. The continued division…

The sponge, a many celled animal, that begins its life as a single-cell, the egg. The continued division of its cells result in the formation of a hollow globe of cells called the blastula, similar to Volvox, and at this point the young larva leaves the parent.

Sponge Develoment

The sponge, a many celled animal, that begins its life as a single-cell, the egg. The continued division…

The sponge, a many celled animal, begins its life as a single-cell, the egg. After division of cells and formation of blastula, the young larva leaves the parent. The next transformation consists of a pushing in of one side. This depression deepens and gradually results in the formation of a two layered sac know as the gastrula.

Sponge Develoment

The sponge, a many celled animal, begins its life as a single-cell, the egg. After division of cells…