The beetle Darwin couldn’t bear to lose

A beetle that once got away from Charles Darwin and seemed to have disappeared from Cambridgeshire forever was rediscovered in Wicken Fen, Cambridgeshire, in 2008, after an absence of more than fifty years.

The beetle that Darwin ‘could not bear to lose’ was the Crucifix Ground Beetle (Panagaeus cruxmajor). We know this because Darwin told the story of trying to hold on to three beetles – one in each hand and one in his mouth – in a letter to his friend Leonard Jenyns in 1846.

For more on the rediscovery, go to the Wicken Fen website.

As a student at Cambridge, one of Darwin’s favorite activities was beetle collecting, and the Crucifix Ground Beetle was one of the greatest prizes for a collector.

In his autobiography, Darwin wrote:

But no pursuit at Cambridge was followed with nearly so much eagerness or gave me so much pleasure as collecting beetles. It was the mere passion for collecting, for I did not dissect them and rarely compared their external characters with published descriptions, but got them named anyhow. I will give a proof of my zeal: one day, on tearing off some old bark, I saw two rare beetles and seized one in each hand; then I saw a third and new kind, which I could not bear to lose, so that I popped the one which I held in my right hand into my mouth. Alas it ejected some intensely acrid fluid, which burnt my tongue so that I was forced to spit the beetle out, which was lost, as well as the third one.

However, it is only from Darwin’s correspondence that we know which species he found on that occasion. Here is the passage from the letter to Jenyns in which the beetles’ identities are revealed:

I must tell you what happened to me on the banks of the Cam in my early entomological days; under a piece of bark I found two carabi (I forget which) & caught one in each hand, when lo & behold I saw a sacred Panagæus crux major; I could not bear to give up either of my Carabi, & to lose Panagæus was out of the question, so that in despair I gently seized one of the carabi between my teeth, when to my unspeakable disgust & pain the little inconsiderate beast squirted his acid down my throat & I lost both Carabi & Panagus!

Who knew that beetle collecting could be so dangerous!