COLOR CHANGES IX SKIX OF LIZARD. 



447 



of the skin of its dorsal surface and then placed it in another 

 vessel under different conditions. 



Two of my animal? I have photographed under the influences 



of the above-mentioned different conditions. From each of these 



graphs were made on one morning, in the case of one 



.f them in the foll\\iir< order: (i) head free, on white back- 



phaliitn. on a white background. About nat. 

 ilocfphaltim. the animal of Fig. I. on a white ba- 

 ll covered head. About \ nat. size. 



ground, 2 lic.nl covered with cap, on white background, (3) 

 he. id five, on bl.uk background, (4) head covered with cap, on 

 \\hiu- lurk-round. (5) head free, on black background, '<> he, id 

 . on \\hiie luck^round. In a second ot photographs, 



t.iken from the other li/ard, the succession of experiment- \\.i- 

 di Herein. but \\ith e.ich exposure the conditions were different 

 from those before and t \\iee the animal was photographed under 

 the >.nne condition-. The photographs taken from animals in 



