Glass sponges

Bubbler. I ve done it widening the end of a glass tube, then puting in the hole with pression a piece of glass sponge (for feet) and... 

Sundar VC, Yablon AD, Grazul JL et al (2003) Fibre-optical features of a glass sponge -some superior technological secrets have come to light from a deep- sea organism. Nature 424 899-900... 

Marine glass sponges such as the hexactinellid sponge Euplectella sp. are one of the most primitive animals in existence. However, they generate a hierarchically engineered cage... 

Figure 1.5 Fine intricate structural design of silica marine sponges (Glass sponge).

Wang, X.H., Schroder, H.C., Muller, W.E.G., 2009. Giant siliceous spicules from the deep-sea glass sponge Monorhaphis chuni morphology, biochemistry, and molecular biology. Int. Rev. Cell Mol. Biol. 273, 69-115. 

Figure 3.2 Silica glass sponge scale bar is 5 cm. (Reprinted from Sundar et al., 2003 with permission from Macmillan Publishers Ltd.)...

The Hexactinellida or glass sponges are characterized by the presence of silica spicules of symmetry 6 (hexactins). They are often deep-water sponges that usually live in zones ranging from the upper bathyal to the abyssal floor and are rarely foimd on the continental shelf, except in Antarctica and other cold seas. However, a few species have been found in submarine caves in the Mediterranean (Vacelet, Boury-Esnault, and Harmelin, 1994 Vacelet, 1996, 1999). 

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