*Pigment cells.*--Branched cells are best studied in the living foot of the frog, where amœboid movements may be seen in them when the light falling on the retina is made to vary in intensity. Permanent preparations are most conveniently made from the pallium of the common snail. The shell is removed, and the pallium snipped out with the scissors. It is then pinned out flat, hardened for a day in methylated spirit, and mounted unstained in Farrant’s medium. They are also well seen in sections of the choroid coat of the eye. *Hyaline cartilage.*--Specimens may be obtained from any joint, from the costal cartilages of young animals, or from the thyroid cartilage and tracheal rings. It may be hardened in spirit. Stain with picrocarmine, eosine and hæmatoxyline, and with methyl violet. *Elastic cartilage.*--Prepared from the epiglottis, or from the cartilages of the ear, _e.g._, of a cat. Harden in spirit. Stain in picrocarmine or in dilute fuchsin. *White fibro-cartilage.*--Obtained from intervertebral disc. Prepare and stain as for hyaline cartilage. *Bone*:-- *Unsoftened Bone.*--Cut as thin a section as possible with a fine saw. Rub the section with the hand on a dry oil stone until it is as thin as possible. Then cement it by Canada balsam (liquefied by warming) to a piece of plate glass and continue the rubbing process with this, examining it now and then with the low power to see if it is thin enough. As soon as it is thin enough it is washed off the slide with methylated spirit, and washed to get rid of the fine bone dust. It should then be transferred to turpentine and may be mounted in balsam. *Softened bone.*--Specimens may be obtained from an amputated limb or from the femur of a cat. Specimens should be decalcified in chromic and nitric fluid, and the hardening completed in spirit. In studying the process of ossification, _e.g._, in the head of the humerus of a kitten, it is best to embed the specimen in celloidin before cutting sections, as the trabeculæ of bone are very delicate, and easily detached. Very beautiful double staining effects may be obtained with either picrocarmine, or eosine and hæmatoxyline, and with eosine and methyl violet. *Bone marrow.*--To obtain good sections of red bone marrow, take a piece of the clavicle or a rib, or of one of the carpal or tarsal bones. Decalcify in chromic and nitric fluid. Embed in celloidin. Stain with eosine and logwood, eosine and alum carmine, or alum carmine and picric acid. Mount in Canada balsam. The various cells present in bone marrow may also be studied by squeezing some fresh marrow from a rib, and making a cover-glass film, and preparing in exactly the same way as is directed in the case of blood films on page 116. *Tooth.*--Best cut _in situ_ from the jaw of a cat. Decalcify in chromic and nitric fluid, and cut both vertical and transverse sections. Stain in picrocarmine, or eosine and hæmatoxyline.