Must be HOT in these suits, note tacky air-conditioner and wire next to the fellow in the middle here. Some "museum." Sponges are alive but don't have any guts! They just sit around with water rushing through them for nutrition. If you want to read some big words, look them up...(gemmules, viviparous, spicules, syncythia, homoscleromorpha, halkieriids, chancelloriids, sessile, calcareous, cchonocytes, asconoid, endosybionts and on and on and on) No wonder we prefer plastic ones. By the way, these are indeed "bobbers" as they would float unless wearing lead shoes.
Three "spongeworthy" postcards, c. 1960 collection Jim Linderman