In Don Marquis’s “archy and mehitabel” stories, which is the cockroach and which the cat?

In Don Marquis’s “archy and mehitabel” stories, Archy is the cockroach, Mehitabel the cat.

Archy was said to have written the stories at night on newspaper columnist Marquis’s typewriter.

He wrote without capitals because he couldn’t reach the shift key. The stories were first collected in archy and mehitabel (1927).