March, 1907.] KnAB : COPULATION OF StEGOMVIA CaLOPUS. 15 



dichery and the small area to which they were restricted led the com- 

 mander to believe that the conditions were exceptionally favorable for 

 accurate observation of their behavior. The warm climate and the 

 abundance of " heating " food, he reasoned, should produce a stimu- 

 lating effect upon the reproductive functions, and in consequence 

 copulation should be more frequent and the opportunities for observa- 

 tion increased. On account of its small size the state-room seemed 

 favorable for this purpose and the first three hours after noon, when 

 the mosquitoes seemed most active, were selected as the most favor- 

 able time. The windows were closed against the wind, and after a 

 sufficient number of mosquitoes had entered, the door was likewise 

 closed. Thereupon the commander, his legs and hands well protected, 

 and armed with a feather to drive off the mosquitoes that threatened 

 his face, spent more than an hour each day in the close heat of his 

 cabin, attentively watching the cloud of mosquitoes which surrounded 

 him. In spite of the time spent nothing was discovered but the pur- 

 suit by the male, which was so much like that in butterflies (as 

 described by Reaumur) that the commander did not consider it worth 

 recording. Convinced that in the end his efforts would be successful 

 he persisted in his observations. He became discouraged, however, 

 when the ship fell into the cold winds off the Cape of Good Hope. 

 The mosquitoes abandoned all the upper part of the ship and fled 

 between decks for shelter, there to suck blood at will. 



Shortly after the Cape had been doubled they reappeared again 

 with the good weather. They all looked well nourished and all that 

 were crushed were found to be filled with blood. The commander 

 thereupon resumed his observations, encouraged further by having 

 found females with the abdomen filled with white bodies which, under 

 a strong lens, he recognized as eggs. These observations proved 

 more decisive than the previous ones. He distinctly saw, flying past 

 him, many couples of mosquitoes intimately united but in a manner 

 different from that in other flies. Their flight slackened at intervals, 

 when it could be seen that they were united face to face, their legs 

 intertwined. From time to time couples fell upon the bureau and 

 again took flight. Many couples that the commander crushed on the 

 bureau-top showed the sexual parts intimately united. Still he thought 

 that he might have been deceived by the manner in which their deli- 

 cate bodies had been crushed together. It was difficult to obtain proof 

 owing to the fact that copulation took place in the air, during rapid 



