306 Trans. Acad. Sci. of St. Louis. 



SUMMARY AND CONCLUSIONS. 



In answer to our inqniries we find: 



1. Males mating with the older or younger female. 



4 males mated the older female (rival seriously defective in 

 two of these cases). 



3 males mated younger female. 



2. Females mating with the older or younger male. 



1 female mated the older male. 



10 females mated the younger male (chosen male deformed in 

 six cases). 



3. Males mating with the beautiful or unattractive female. 



4 males mated the beautiful female (in two of these cases, rivals 



in very bad condition; in other two, of equal age). 

 1 male mated unattractive female (chosen female was younger). 



4. Females mating with the beautiful or unattractive male. 



1 female mated the beautiful male (younger). 



5 females mated the unattractive and deformed male. (All of 



which were either younger or of the same age as the rival.) 



5. Females mating with the normal or wingless male. 



3 females mated the wingless male (all younger). 



6. Females mating with antennae removed. 



7 mated. 



1 did not mate. 



7. Males mating (a) with one-half of each antenna removed. 



7 mated. 



1 did not mate. 



(b) With one antenna removed. 



12 did not mate. 

 1 doubtful. 



(c) Both antennae removed. 



11 did not mate. 



By this time the reader must feel how inadequate are 

 the theories in explaining the real occurrences in the liv- 

 ing material. 



It is at once evident that we do not yet know the attrac- 



