312 PROCEEDINGS OF THE ACADEMY OF [Apr., 



(6) Other Ants and Hornets Examined. — The groups of pores in the 

 other specimens of Formica and Camponotiis examined are tolerably 

 constant in number and position. They are so similar to those of 

 the females of Formica, that only the total number of pores will be 

 given. Counting the pores for all five individuals in each set, the 

 total average number of pores is as follows: males of Formica — ^legs 

 356, legs and wings 892; major workers of Formica — legs 332; 

 dealated females of Camponotus — legs 317; males of Camponotus — • 

 legs 322, legs and wings 1,090; major workers of Camponotus — legs 

 331; minor workers of Camponotus — legs 314. In regard to the 

 total number of pores on the legs, it is thus seen that there is practi- 

 cally no difference between the number on the legs of workers and 

 queens and only a few more on the legs of males, but the wings of 

 males have many more than do the wings of females. (For more 

 details see table, page 331.) 



The groups of pores in the worker hornet {Vespula maculata) are 

 also quite constant in number and position and resemble those of the 

 worker honey bee more than those of an ant. The group on the 

 femur is always double, consisting of two rows of pores widely divided, 

 and for this reason each row is regarded as a separate group. Groups 

 Nos. 7 and 9 on the leg of an ant also each consist of two rows of 

 pores, but since the two rows lie side by side they may be regarded 

 as only one group. Group No. 6 of an ant is a straight row, while 

 the pores of the same group of a hornet are bunched. The other 

 groups of the hornet are quite similar to those of the honey bee. 

 'The total number of pores for the hornet examined is 1,957. (See 

 table, page 333, for details.) 



The pores of an ant vary more in size than do those of the hornet 

 or honey bee. Group No. 8 (Plate XI, fig. 3)- on the trochanters well 

 illustrates this. Here the largest pore is at least five times the size of 

 the smallest one. Those on the tibia3 (fig. 4) also vary much. Those 

 on the wings (fig. 5) vary only slightly in size. In proportion to the 

 sizes of an ant and of a worker honey bee, the pores of the ant are 

 much larger. The pores of a hornet are proportionately as large 

 as those of the honey bee. 



2. Structure. 



(a) E.vternal Structure. — When examined under a low-power lens, 

 the olfactory pores may be easily mistaken for hair sockets from 



2 All figures, except text figures 1, 2, and 3, are numbered consecutively on 

 Plates XI and XII. 



