This is the first shot that I got when I discovered a pair of Leopard Slugs (Limax maximus) beginning to mate in my garden. They were suspended by about a metre of the slime shown in the photo, and anchored from the bark of a tree trunk. They were about half a metre off the ground. At this stage they had finished producing the slime and were about to start really mating.

In this shot you can see that part of the sexual organ has been 'everted' by the slug that's lower down. It is a very beautiful thing - translucent white, almost blue, like those photos of ice caverns you see.

The other slug has also begun to evert the organ. You can see that it comes out from around the side of the head. Well those beautiful organs have found each other and they've entwined a few times. You can see another feature of the organs - they are flanged.