Selection of various histological preparations of cuts of the brain made by Cajal. 1. Handwritten label: No. 9. Medulla of a bird. bb; 2. Handwritten label: cat, 8 days. The tuber cinereum region; 3. Handwritten label: 2 Paralytic. Microglia; 4. Handwritten label: mouse, 15 days. Olivocerebellar tract. Series of 2.