162 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS (11) Magnusson, B., and Kligman, A.M., The identification of contact allergens by ammal sasay. The guinea pig maximization test, J. Invest. Dermatol., 52, 268-76 (1969). (12) Maguire, H. C., Jr., Mechanism of intensification by Freund's complete adjuvant of the acquisition of delayed hypersensitivity in the guinea pig, ImmunoL Commun., 1, 239--46 (1972). (13) Landsteiner, K., and Chase, M. W., Studies on the sensitization of animals with simple chemical compounds. VII. Skin sensitization by intraperitoneal injection, J. Exp. Med., 71, 237-45 (1940). (14) Landsteiner, K., and Jacobs, J., Studies on the sensitization of animals with simple chemicals, Ibid., 61, 643-56 (1935). (15) Landsteiner, K., and DiSomma, A. A., Studies on the sensitization of ani•nals with simple chemical compounds. VIII. Sensitization to picric acid subsidiary agents and mode of sensitization, Ibid., 72, 361-6 (1940). (16) Buehler, E. U., Delayed contact dermatitis in the guinea pig, Arch. Dermatol., 91, 171-5 (1965).

J. Soc. Cosmet. Chem., 24, 163-180 (March 2, 1973) Slit-Lamp Examination of Experimental Animal Eyes. I. Techniques of Illumination and the Normal Animal Eye THOMAS O. McDONALD, M.S.,* HENRY A. BALDWIN, B.S.,* and C. HAROLD BEASLEY, M.D.* Presented May 25, 1972, Seminar, Los Angeles, Calif. Synopsis--The SI,IT LAMP is an indispensable tool for the ophthalmologist and for the ex- perimental researcher utilizing the eye. The purpose of this paper is to describe briefly the slit lamp and accessories, disCriss uses and limitations of the type of slit-lamp ILLUMI- NATION for visualization of the eye, and describe the normal:ANIMAL EYE. Since the use of the slit lamp can be easily mastered, its use in evaluating the eye in experimental studies should be irnplement6d. Critical observation of the eye utilized in OCULAR IRRI- TATION studies for pharmaceuticals, cosmetics, and other formulations can be accom- plished with the aid of the slit lamp. INTRODUCTION The slit-lamp microscope is an instrument of this century (1, 2). It has evolved from an exclusive research device to an indispensable tool for the ophthalmic practitioner. Recently it has been adapted for use in the experi- mental ophthalmic area. The slit lamp can become a useful tool for evaluation of formulations for ocular damage in animal test models. Since many cosmetic formulations may * Science and Technology Division, Alcon Laboratories, Inc., P.O. Box 1959, Fort Worth, Tex. 76101. + 1212 West Presidio, Fort Wc'rth, Tex. 163