36 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 65 



top of the head (fig. 10, c 13 ). Several were seen on each palpiger 

 (figs. 7 and 8, c 14 ) and several, marked c 13 , on the ventral surface and 

 sides of the mentum. Eighty-three hairs marked c 16 were counted on 

 the tongue. The most of these lie on the ventral side. Several inner- 

 vated hairs marked c 17 were seen on each side of the labrum near the 

 anterior edge. All the large hairs marked c 18 on the maxillse and 

 labial palpi seem to be innervated. 



(b) PEGLIKE HAIRS 



Variety d. Those marked d ± and d 2 are found only on the flagella 

 of the antennae. 



Variety e. Those marked e x are found on both sides of the maxillse 

 near the maxillary palpi. There are perhaps 50 on each maxilla. 

 Only a few marked e 2 are present on the base of each labial palpus. 



Variety f. Several marked / occur at the distal end of each max- 

 illa and labial palpus. 



In conclusion under this heading it is seen that all the true hairs 

 on the tongue are innervated, while practically all on the maxillse, 

 labial palpi, palpigers, paraglossse and mentum are connected with 

 nerves. All of those near the anterior edge of the labrum and all on 

 the mandibles, except two varieties of large hairs (figs. 6 B, Hr 1 and 

 10, Hr 2 ), are also connected with sense cells. 



Table VIII is a tabulated summary of the disposition of the 

 innervated hairs herein discussed. The blank spaces mean that hairs 

 were not looked for on the appendages recorded. 



4. Disposition of the Olfactory Pores 



Olfactory pores (figs. 7 and 8, Por) were found irregularly dis- 

 tributed over the entire surface of the mandibles (Md), except on the 

 biting surfaces (BS) and between the two ridges (Rg) . Very few 

 occur on the proximal half of this appendage, while they are quite 

 abundant on the distal half. There are at least 150 on each mandible 

 of the workers. 



On the tongue (fig. 7, Gls) olfactory pores were found only on the 

 dorsal side at the base. These are arranged in two groups, each 

 group being located on a prominence just posterior to the notch (Nt) . 

 A groove (Gv 2 ) connecting with the two notches runs between the 

 two prominences and continues as a shallow depression (Gv 3 ) to the 

 base of the mentum (Mt). The number of pores in either group on 

 any given tongue is almost constant, and the individual variations 



