I thought I just read a post recently that explained the same misconception, but rather than dried sperm it was said that the things that people were commonly calling "sperm plugs" were hemipene casts, like a shed from the hemipene. I can't recall exactly which post that was in, and please correct me if I'm wrong, but that was the impression (no pun intended) that I got . Does anyone else recall that conversation or have any info on whether there is such a thing as a hemipene cast?