How do snakes have sex?

Asks Rissa.  At bedtime.  Because she's crazy.

"Mummy, how do snakes actually have sex?"

"Pardon?"   Gear shift.  I was mildly confused as the last thing she'd said had been:

"Mummy what if you just started sprouting extra ears all over your head?"

As to the snake sex thing, I really hadn't a clue.  I was pretty much in the dark as to the logistics of reptile mating.*  "Well I imagine the male has a penis and the female has some sort of vagina..."

"Mummy!!!!  What if the male snake IS the penis?"

I think I then made a Scooby Doo sound.

Ruh??

"No seriously Mummy!  It totally could be true!  The male snake would BE the penis and then he would just..."

"Put his entire body inside the female?"

"Maybe....  Although that would probably be a lot for a female snake to take...  Wait!  Wait!  What if all snakes are just males..."

"They aren't."

"But what if they were?"

"So basically, if there were no female snakes, and the male snake IS the penis - what you're saying is that there would be a bunch of penises slithering around on the ground?"

"Mummy.... EEEEEEEEEEW!!"

"Dude.  You totally started it."

* Oh and just in case you were wondering, male snakes have two-headed penises.  The hemi-penis.  (See the diagram below - third section up from the tail.)  When I told Rissa that - she said there needed to be a different word.  "Plurenis" is what she came up with.