1919] Mclndoo: Olfactory Sense 73 



ocellar pore {Oa), and subcellar pores a (SOa), b {SOb) and 

 c {SOc) ; on the dorsal and ventral surfaces, respectively, of the 

 mandible: the mandibular pores a {Mda) and b (Mdb); on the 

 ventral surface of the labium: the labial pores a, b and c {Lba 

 to c) ; and on the dorsal surface of the labrum : the labral pore 

 (Lra). Relative to the maxilla they are as follows: On the 

 ventral surface of the stipes: the maxillary pore a {Mxa); on 

 the dorsal surfaces of the palpiger, first segment of the maxillary 

 palpus and maxillary lobe, respectively: the maxillary pores 

 b, c and d (Fig. 8, Mxb to d) ; on the ventral surfaces of the first, 

 second and third segments of the maxillary palpus, respectively : 

 the maxillary pores e (Fig. 2, Mxe) and/ to 7 {MxJ to 7). On 

 the ventral surface of the second or terminal segment of the 

 antenna, near the proximal end at the outer side, lies the 

 antennal pore (Afita). 



Relative to the thorax and abdomen, the pores are located 

 and may be named as follows: On the anterior surface of thg 

 femur: the femoral pores a and b (Fig. 3, Fea and Feb) ; on the 

 posterior surface of the femur: the femoral pore c (Fig. 4, Fee); 

 on the posterior surfaces of the tibia and tarsus, respectively: 

 the tibial pore (Fig. 4, Tba and tarsal pore {Ta) ; on the tergum 

 of the prothorax: the thoracic pores a, b and c (Fig. 5, TIa to 

 c) ; on the tergum of the last abdominal segment : a single pair 

 of pores, the abdominal pores (not drawn) ; and on the dorsal 

 and" ventral surfaces, respectively, of the anal proleg: the 

 anal-proleg pores a and b (Figs. 6 and 7, A Pa and APb). 



Relative to the pores on the head of the army worm, the 

 subocellar pores (Fig. 2, SOb and SOc) and mandibular ones 

 {Mdb) are the most difficult to be found. While the former lie 

 in almost transparent chitin, the latter one lies in very dark 

 chitin; all of these, as well as the pair (Fig. 1, Mda) on the 

 dorsal side of the mandibles, seem to have been overlooked by 

 other observers. The ultraposterior ones (Fig. 1, Z7-Pa.and 

 UPb) are easily mistaken for the secondary setae (Ai and Ao) 

 and can only be distinguished from them by aid of a high-power 

 lens. Perhaps all of the pores on the labium and maxillae have 

 been seen by systematists, but it seems that the third labial 

 pair (Figs. 2 and 20, Lbc), and maxillary pores b, g to j (Figs. 

 8 and 9, Mxb, g to j) have never been drawn. As far as known 

 to the writer, those on the legs, last abdominal segment and on 

 the anal prolegs are here reported for the first time. 



