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PROCEEDINGS OF THE ACADEMY OF 



[Apr., 



studied, and this insect is also tiie largest one examined. The pore 

 apertures are actually visible in only four of the pores drawn (figs. 

 29 and 31). The pores of the muddobber (figs. 33 to 41) are the 

 second largest ones studied. Four pores (fig. 41) were found on the 

 thorax at the base of the niche of the front wing. 



All the pores of the ant, hornet, and muddobber described in the 

 preceding pages may be compared with a typical pore (fig. 42) from 



Fig. 3. — Diagram of a transverse-longitudinal view of a small portion of 

 femur {¥) and about two-thirds of trochanter (Tr) from hind leg of female of 

 Formica, showing the internal anatomy of the leg and innervation of groups of 

 pores, Nos. 7, 8 and 9. 



the tibia of a worker honey bee. All drawings of these pores are 

 enlarged the same number of times. 



V. Physiology of the Olfactory Pores. 



To ascertain whether the pores, which have been studied, are 

 actually the organs in ants and hornets that receive odor stimuli, 

 the wings and legs of many individuals were mutilated. The behavior 

 of these mutilated insects was carefully studied and they were tested 



