Illustration for Doctor Doolittle (The Doctor at the Zoo)

Charcoal on off-white wove paper

Black and white chalk on tan wove paper; verso: black chalk

Red chalk on cream wove paper

Black and white chalk on gray-green wove paper

Graphite and blue, purple and black ink on blue paper

Graphite and red pencil on off-white wove paper

Graphite and brown chalk

Charcoal on cream laid paper

Black ink, watercolor, and gold paint on tracing paper

Graphite

Black fiber-tipped ink and Letraset

Ink on yellowish paper mounted on cardboard