416 



Mr. F. Merrifield and Mr. E. B. Poulton 



The effects of a dull surface of perforated zinc (9 — 11) 

 and of hroivn paper (12) were, as might be expected, 

 practically the same as those of black. 



Salmon paper (13) acted like orange (14 — 29), and 

 produced the lightest and greenest form of pupa. The 

 results of so many experiments with orange are very 

 striking, especially as a very deep reddish-orange surface 

 paper was employed. 



Yellow (30 — 40) also produced striking results in the 

 same direction, but not equal in the proportion of the 

 greenest pupse, to those of orange. 



Green cahbage-leaves (41) acted like orange. 



Experiment 42 was very mixed, the pupse being, almost 

 all of them, fixed to a tvJiite surface in a dark purple box 

 in a very dim light. They were strongly on the light side 

 of intermediate. 



White (43 — 48) has been already described as producing 

 pupse on the dark side of intermediate (see p. 409). There 

 are, however, some few marked exceptions in both Mr. 

 Merrifield's and my experiments, in which the lightest and 

 greenest pupas were obtained. 



Thus Mr. Merrifield's and my experiments in 1898 



