He looked with a naturalist's interest at their grimacing faces, in which he discerned traces of their occupations and appetites; he listened also to their inane chatter, just as he might have tried to catch the meaning of a cat's mew or a dog's bark.

At this period he was occupied with comparative natural history, applying to the human race the observations which he had made upon animals with regard to the working of heredity.
While he was in the yellow drawing-room, therefore, he amused himself with the belief that he had fallen in with a menagerie.

He established comparisons between the grotesque creatures he found there and certain animals of his acquaintance.

The marquis, with his leanness and small crafty-looking head, reminded him exactly of a long green grasshopper.
Vuillet impressed him as a pale, slimy toad.

He was more considerate for Roudier, a fat sheep, and for the commander, an old toothless mastiff.
But the prodigious Granoux was a perpetual cause of astonishment to him.
He spent a whole evening measuring this imbecile's facial angle.