Ircinia:

Genus with filamentous spongin threads filling the choanosome, which make the sponges extremely tough and difficult to tear; reticulated sand pattern on surface.

Ircinia felix

Typical form (f. felix) of species crustose, with raised oscula, or massive, with 1-2mm conules on surface. Forma fistularis with simple erect holoow branches and terminal oscula; f. acuta conical or massive, with elevated oscula, with large (2-4 mm) conuli. All forms grayish to chestnut-brown, up to 25 cm. With a very distinctive odour when exposed to the air.