1914.] NATURAL SCIENCES OF PHILADELPHIA. 323 



9. Summary. 



From the preceding pages it is seen that probably not more than 

 21 per cent, of the pores on the wings of female ants are lost at the 

 time the wings are shed and that the remaining 79 per cent, of the 

 pores are not prevented from functioning because the wings break 

 off at a weak place (text fig. 1 and Plate XI, fig. 25, xx, yy) in the 

 chitin just distal to the groups of pores. The wound caused by the 

 wings breaking off cannot affect the sense cells connected with the 

 pores, because a heavy layer of chitin separates them from the external 

 air. Sections through the thorax of an old dealated female ant show 

 that most of the muscles in the thorax have degenerated, but the nerves 

 running to the wings are still present and the pores in the stubs of the 

 wings are still connected with sense cells. This indicates that the 

 sense organs in the stubs of the wings function throughout the life 

 of the ant. 



All of the results obtained in the experiments on normal and 

 mutilated insects are summarized in the following table. To make 

 the table complete for Hymenoptera and for comparison, the data 

 from the writer's former paper concerning the worker honey bee are 

 appended. The ''three odors" used are those from oil of pepper- 

 mint, oil of thyme, and oil of wintergreen. The "six odors" used 

 are those from oil of peppermint, oil of thyme, oil of wintergreen, 

 honey and comb, leaves and stems of j^ennyroyal, and formic acid. 

 It will be noted that when the antennae of any of the insects listed 

 in the table are mutilated, the insects are abnormal in behavior; 

 but when the pores on the legs and wings are covered, the insects 

 are normal in behavior. The reaction times obtained by using 

 insects with mutilated antennae are slower than those ol^tained when 

 umnutilated individuals are used, but it is quite possible that the 

 slower reaction times are caused by the abnormal behavior of the 

 insects and are not due to the theory that some of the olfactory 

 organs are prevented from functioning. When the wings are pulled 

 off artificially, about three-fourths of the pores on these appendages 

 are lost and the reaction times are slightly slower. When the pores 

 on the legs and wings are covered, the reaction times are more than 

 doubled, while in the honej^ bee the reaction time is increased twelve 

 times. It was impossible to prevent the ants from removing most 

 of the vaseline from the legs. 



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