298 Trans. Acad. ScL of St. Louis. 



Experiment 42. — June G, 11 :00 P. M. 



(^137. Age 7 days 10:30 hours. 



c^ 145. Age 2 days 7:00 hours. One antenna removed. 



9 146. Age 2 days 6:00 hours. 



Object. — To ascertain whether the female will mate 

 with a normal male of 7 days, or one 2 days old with one 

 antenna lacking. 



RestiUs. — June 9. They have been together for 3 days without 

 mating. As the cause for this we would suggest that one male is rather 

 old, and the other, having only one antenna, may be unable to locate 

 the female. To make sure that the fault lies with the males and not 

 with the female, they are removed, and male 172 placed in their stead.— 

 June 10, A. M. This pair found in copulo. 



Experiment 43. — June 7, 9 :00 P. M. 



cJ 154. Age 2 days 4:30 hours. A wingless insect which has 



left off mating only a few minutes previously. 

 (5" 147. Age 3 days 3:50 hours. Antennaless. 

 9 164. Age day 5:30 hours. 



Object. — To see whether the female will mate with an 

 already mated, wingless male, or an unmated, antennaless 

 one. 



Results. — June 10. Mating has not yet taken place. 



This shows that, in this experiment at least, the mated 

 male as well as the antennaless one cannot mate. 



Experiment 44. — June 7, 10 :00 P. M. 



5 149. Age 2 days 9:00 hours. 

 c?143. Age 3 days 6:30 hours. 

 (^165. Age day 5:30 hours. Antennae removed. 



Object. — To find whether the female will mate with the 

 normal male or the younger antennaless one. 



Results. — June 11. After being together for almost 4 days, mating 

 has not taken place. If it be impossible for the antennales male to 

 mate, male 143 is yet to be had.^ 



Experiment 45. — June 8, 10 :00 P. M. 



(^166. Age 1 day 5:00 hours. 



9 171. Age day 5:00 hours. Antennae removed. 



Object. — To find if an antennaless female will mate. 



