This is my SECOND try at posting multiple pics. on kingsnake so I hope it works.
Here she is when I first found her giving birth.

Here she is about 10 minutes later.

Notice that when first born, they are over 1/2 inch long and very thin. Then they eat the egg casing and grow shorter (to about 1/3 inch) and wider as fluids pump through their bodies.
I've seen hisser births multiple times, but never had my camera ready at the time-or they were in a place that I couldn't photo very good. Hope you like the pics.
Rodney

