REVISION OF STREPS1PTERA — PIERCE. 55 



to my comment on fertilization). The entire body is a-quiver, 

 especially the tarsi. During this period I noticed no movement of 

 the mouthparts. 



Before it had lived an hour the sound became very diminutive, 

 and finally the wings ceased to vibrate. Occasionally, however, 

 considerable movement was manifested. 



When about two and a half hours old a violent movement took 

 place for several minutes, which involved mainly foot action. The 

 antenna?, mouthparts, elytra, and body w r ere combed in quick suc- 

 cession by the legs, and finally the insect lost all power of retention 

 of its foothold. It partially regained this, how r ever. It was then 

 that I was able to see a distinct movement of one of the mandibles, 

 and to observe that each part of the thorax was capable of move- 

 ment by virtue of the elastic yellow commissures uniting the chitinous 

 parts. This was especially true of the prothorax. The abdomen 

 at the end of this period had shrunk to one-half of its original length. 



The final period consists of a faint quivering of legs and antennas, 

 the insect being upon its back. 



From these observations several important points may be deduced. 



1. The independent movement of the antennal branches indicates 

 that the antennae form a very important function in the life of the 

 insect. 



2. The dowmvard and forward movement of the abdomen indi- 

 cates that the fertilization takes place with the male in an erect 

 position as recorded for Cratvfordia pidvinipes. 



3. Although not stated in the preceding paragraphs, it was noted 

 that the last tw T o pair of legs assumed the greater part of the burden 

 of supporting the body. 



4. The reason for the insects keeping up a constant buzzing sound 

 throughout the active portion of its life must remain unexplained. 



5. The presence of innumerable sense bodies on the antenna? indi- 

 cate to the waiter the probability that these organs can detect the 

 presence of the host insect by its sound, or perhaps of the female 

 parasite by its odor. 



6. The violent combing of antenna?, mouthparts, elytra, and body 

 would indicate a highly sensitive integument, and suggest that per- 

 haps the maxillary palpi at least also serve as sensory organs. 



7. The movement of the mandibles proves them to be not entirely 

 useless. The palpi must have some function, as they are never in 

 tw T o specimens placed in the same attitude. 



8. The presence of elastic commissures between the head and 

 three thoracic segments w r ould indicate a line of descent direct from 

 the Thysanura with all of the antecedents lost. Tins point is strength- 

 ened by the passing through the Campodeoid type in the larva. The 



