A Question of Illustration

I'm working on my first novel, and I've run into a dilemma: my brain not only percolates in words, it also spews pictures. I have tons of small drawings, mostly pen-and-ink that I've begun to incorporate with my writing. They're usually pictures of unusual creatures or buildings that appear in the story, and are mostly no bigger than a business card (think the illustrations in the older editions of Alice in Wonderland, or young adult novels like Un Lun Dun by China Mieville) So here is the question: Do I include these little illustrations when I send sample pages? Does it make any difference to an agent or a publisher if I include them or leave them out?

Thanks for any advice in advance :]

Thank you all very much for your help, i'll stick to word pictures for right now :] I really appreciate it!