DARWINISM ATTACKED. 123 



"We are therefore forced to conclude that the melanic 

 coloration of the male has not been brought about through 

 the agency of sexual selection on the part of the female." 



More recently Mayer (and Soule) 9 repeated these experi- 

 ments on a more extensive scale and with some variations 

 in character. Fifteen hundred cocoons of 



Mayer and 



Scale's expert- Promethea were collected in the winter of 1901- 

 02 and hung in trees so that the issuing moths 

 might fly about unconfined. "About six hundred males 

 emerged from the cocoons and the wings of about one-half 

 of them were painted with scarlet or green ink, while the 

 others were allowed to remain normal in colour. It was 

 evident that the males whose wings were scarlet and green 

 succeeded fully as well in their attempts to mate as did the 

 normal males." 



Experiments were also tried with the moth Porthetria 

 dispar, in which the male is brown and the female white. 

 The experiments showed that males with wings painted 

 scarlet or green were accepted as readily as normal males, 

 "but that males with the wings cut off were more apt to meet 

 with resistance from the females than perfect males were. 

 From these experiments Mayer and Soule conclude that the 

 mating instinct in the males of C. promethea and P. dispar 

 is a phenomenon of chemotaxis. Sexual selection on the 

 ground of colour alone does not affect it, and there is no 

 associative memory connected with it. 



To these experiments may be added the observations of 



Douglass, 10 who found that females of the wall-lizard, 



Laccrta muralis, showed no preference what- 



Expenments eyer among - the variable patterns exhibited bv 



on lizards. f 1 1 



males in breeding-coat. Diirigen 1 observed 

 that male lizards without tails are accepted readily by 

 females. 



Finally, also, of the nature of objections to the sexual 

 selection theory are the replacing or substutionary explana- 



