It is estimated that only one percent of museum collections are on display at any given time, so, when I took a lift down to the basement archives of Tūhura Otago Museum, I knew Atlantis awaited me, though I wasn’t to know that my heart would swell over a sea sponge.

You may be wondering how I got into the archives. Is Dunedin’s security that relaxed? Does Constance really have interests outside of Leonard Cohen? Tūhura periodically allows the public to descend into their windowless basements. I do love a peek behind the curtain. You should try it! You, too, might find yourself in a temperature-controlled room, falling for a sea sponge and dreaming of bathing within it. 

Colloquially known as Neptune’s Cup (gorgeous name), the Cliona patera artefact was propped up with a piece of perspex atop four metal rods, sitting on a storage shelf beside whale bones nestled on pillows. This huge chalice-shaped sea sponge was once used as a baby’s bath (swoon). The sponges became so popular with collectors that, in the 1900s, this natural goblet was thought to have been driven to extinction, due to over-harvesting. 

The Wikipedia page for Cliona patera only gave me a few centimetres of information to go on, so I had to dive in further to scratch this itch. I put on my cerebral scuba suit and took to Google Scholar. Cliona patera had not been seen alive for over a century, the last time being in 1908. In a surprising change of tide, one hundred and three years later, during a routine dive in 2011, biologists discovered the sponge growing off the shores of Singapore. Phew. 

First described in 1822 in a paper by Major-General Thomas Hardwicke, the goblet-shaped sponge, which can reach 1.5 metres in height and width, anchors itself to the ocean floor and feeds on a diet of plankton. 

The Neptune’s Cup at Tūhura Otago Museum is almost a metre in both height and width, ample room to bathe a big baby. There are only two other Cups in museum collections globally, one at Museo Civico di Storia Naturale Giacomo Doria (Genoa, Italy), and the other at Naturalis Biodiversity Center (Leiden, The Netherlands). Excitingly, the latter was photographed by Jan den Doop in 1925. He photographed Pietje (wife of his friend, zoologist Frans Cornelis van Heurn) using this special sponge as a bath for their daughter, Johanna Maria. 

In 1928, 20 years after the last sighting of a live Neptune’s Cup, a series of collectable cigarette cards by W.D. and H.O. Wills, titled “Wonders of the Sea”, featured Cliona patera. Currently, this card is being sold on ebay.co.uk for a mere £3.99. (Update—I bought one—don’t fret, there is still another available, from a different seller.) 

This bathing in a sea sponge imagery got me thinking about the seaweed bathhouses in Ireland that cropped up all over the coast from the 1700s. At its peak, during the Edwardian era, around 300 seaweed bathhouses were operating in Ireland. 

Just think, big pools of steaming-hot seawater broth, swirling with seaweed. One of the most famous of these is the Enniscrone Cliff Baths, which, now fallen into ruin, resembles a derelict castle. It is perched on the shore. (Those are some enviably low carbon-miles of transporting seaweed from shore to bath.) 

Back to Neptune’s Cup; speaking of ocean-dwellers large enough to clamber inside of, about a month ago, I was sent, on Instagram direct messages, by multiple people, an image of an extremely large shell that was being used as a pulpit in a church. The image had no credit. I had to know, where was this magnificent site? Was it an AI-generated image, or did this location really exist? (These days, it’s hard, and annoying, to figure out.) I scoured the internet, reverse-image searching, clicking every link, using all of the internet research tools in my repertoire. I did not raise my eyes from my laptop screen for two hours. 

The only traces I could find of this magnificent shell were always the same photo, and never with any location information. Don’t worry, dear reader, this girl doesn’t give up that easily. Just yesterday, I solved it. I found the Youtube channel of the church. A two hour sermon was uploaded two weeks ago to their audience of 288 subscribers (now 289—they got me). 

At around the 7 minute mark, you can see the preacher ascend the stairs into the giant shell. I have found the church’s address too; if you happen to be in northern Papua, you can see it for yourself. 

I’ll come clean; I respect sponges, but, usually, they kind of make me yawn. However, Neptune’s Cup got me hook, line, and sinker. Now, I dream of being bathed in a sponge. I have filed this in my ‘Dream Situation List’, along with soaking in a bath of seaweed broth, and visiting the giant shell pulpit. The List also has two more achievable dreams: sleeping on a mattress made of straw in a barn, and drinking milk sprayed into my mouth directly from an udder.

With thanks to Tūhura Otago Museum.