It is important to understand this cartoon in the context of the previous entry, "Nincompoopiana---The Mutual Admiration Society," because it features a recurring character: Jellaby Postlethwaite. In this cartoon, Jellaby is sitting at a Pastrycook's by himself, and orders a cup of water to put his "freshly-cut Lily" in. The waiter asks if he wants anything else. Jellaby replies with "Thanks, no! I have all I require, and shall soon have done!" This cartoon further pokes fun of Jellaby as this male æsthete who is obsessed with the beauty of nature, and the beauty of surfaces. This, along with his physical characteristics (mentioned in "Nincompoopiana"), feminizes and queers him compared to societal standards of masculinity during the time. Again, the Wilde parallel appears: a man obsessed with nature, but specifically flowers, this stereotypically frilly and "female" thing. The lily is one of the flowers that is repeatedly shown throughout the Oscar Wilde caricatures of 1882-1883, along with sunflowers, making both flowers symbols of aestheticism.

Source:

Du Maurier, George Louis. "An Æsthetic Midday Meal: George du Maurier Cartoons from Punch magazine." Punch, 17 Jul. 1880, https://magazine.punch.co.uk/image/I0000bUqTuRftskI.