There are two tortoises on the patio: a male and a female. Zlak! Zlak! their shells strike each other. It is the season of their love-making.
The male pushes the female sideways, all around the edge of the paving. The female seems to resist his attack, or at least she opposes a somewhat inert immobility. The male is smaller and more active; he seems younger. He tries repeatedly to mount her, from behind, but the back of her shell is steep and he slides off.
Now he must have succeeded in achieving the right position: he thrusts with rhythmic, cadenced strokes; at every thrust he emits a kind of gasp, almost a cry. The female has her fore-claws flattened against the ground, enabling her to raise her hind part. The male scratches with his fore-claws on her shell, his neck stuck out, his mouth gaping. The problem with these shells is that there’s no way to get a hold; and, in fact, the claws can find no purchase.