The following diagrams come from Invertebrate Zoology, by Rupert and Barnes. The photos are my own.

Here is a close view of an asconoid sponge from our aquaria in the lab - similar if not identical to the one in Fig 5-3 B above:

Here (below) is a photo I took of a boring sponge living in a rock in our marine aquaria in the lab (this sponge can be seen on the left side of the anemone tank, close to the glass near the rear, sort of near the top of the tank). The sort of circular yellow objects are sponge tissue. They are sort of like snorkels that grow to the surface of the rock for water intake (the ones without a well-defined hole in the center) and water outflow (the ones that look like hollow tubes).

The red and purple colored areas are coralline algae, the whitish area in the top right is an encrusting sponge of a different species living on the surface of the rock, the green balls are a green alga called Valonia, and the brown tubes and white flowery/feathery looking things are tube worms.