NSFW substance coming out of my lettuce

[DrMike27]

I let one of my Bibb lettuce plants bolt and it has been giving me some great seeds. When I was harvesting the mature seed pods today, I noticed this really sticky white liquid coming from the plant at the sites that I pulled off the pods. Any idea what this is? I don’t know how else to describe it other than it has kinda the consistency of...uh...just look at the pics.

 

[Mr_Yan]

I've always assumed it is just a version of the same white latex sap that moves though lettuce any other time of year.

The milky white sap of lettuce is a natural latex fluid which will help scab over damage to the plant among other things. Look at the binomial name of lettuce - Lactuca sativa - and the word latex, and the various words lactate, lactose, lactace - they all have to do with milk and milky looking fluids. All these words tie back together with the dead language Latin.