The identification of leather species by means of follicle pattern is described, beginning with the preparation of microscopic cross-sections. The relative merits of canada balsam, methacrylates and paraffin wax for different types of leather are discussed. The possibility of using sizes of fibre bundles as an aid in identification is illustrated, followed by the characteristics follicle pattern of different animals. (note: illustrations not published). The discussion covers mainly problems of identification of different animals, and determination of animals used to prepare vellum when no follicle pattern can be seen (said not to be possible).