Figure 35 from: Manconi R, Cadeddu B, Ledda F, Pronzato R (2013) An overview of the Mediterranean cave-dwelling horny sponges (Porifera, Demospongiae). ZooKeys 281: 1-68. https://doi.org/10.3897/zookeys.281.4171

Figure 35 - Hyrtios collectrix. a detail of a fibre tract showing a scanty amount of spongin with a wide variety of mineral debris embedded, including also spicules of many other sponge species b foreign materials embedded in the sponge surface c pictorial representation of a sponge cross section close to the surface with flagellate chambers represented as terminations of a tree-shaped aquiferous system. a–c modified from Schulze (1879b)