"You wanna cookie, Polly?" (pg. 297)
affectation (pg. 46) -- The act of taking on or displaying an attitude or mode of behavior not natural to oneself or not genuinely felt.
we're not looking for 'Ozymandias' here (pg. 84) -- Poem by Shelley having to do with Egypt.
res gestae (pg. 90) -- Latin for "things done".
...at a workman who was serenely pruning a leggy hibiscus trellised along an archway... (pg. 175) -- The world "Hibiscus" was crossed out and "boug." penciled in. I guess someone thought a bougainvillea would be more likely to be on a trellis than a hibiscus. And from my research, I agree. But exactly is a "leggy" hibiscus?
"You have the world's most absolutely gorgeous submaxillary triangle, did I ever tell you that?" (pg. 93)
Joly emerged from the doorway of the Musée Thibault and avidly, gratefully lit up another Gitane, getting it out of the pack, into his mouth, and alight with what seemed one motion. (pg. 173)
cockamamies (pg. 182) -- Comes from the word decalcomania, temporary "tattoos".
Biscuits Mckay (pg. 260) -- Maybe some kind of cookie, but no trace on the internet. Their motto is "C'est OK!"