I just read Coders at Work and here's an excerpt from the interview of L. Peter Deutsch about this quote:

Seibel: I think Larry Wall described it as bowl of oatmeal with fingernail clippings in it.

Deutsch: Well, my description of Perl is something that looks like it came out of the wrong end of a dog. I think Larry Wall has a lot of nerve talking about language design -- Perl is an abomination as a language. But let's not go there. (...)