PD288-291. Silly jisms

Logically, what else should I call them?
There once was a man from Calcutta
Who used to beat off in the gutta
The heat of the sun
Affected his gun
And turned all his cream into butta.

There once was a blackguard from Sandem
Who was making his girl on a tandem.
At the peak of the make
She jammed on the brake
And scattered his semen at random.

A geneticist living in Delft
Scientifically played with himself,
And when he was done
He labeled it: Son,
And filed it away on the shelf.

There once was a Swede in Minneapolis,
Who worried his sex life was hapless:
The more he would screw
The more he'd want to,
And he feared he would soon be quite sapless.