BRAIN OF THE WHITE ANT 



581 



and an opening to the exterior, seem to indicate that this gland 

 probably produces secretion and is therefore functional. The 

 true adult frontal gland in this respect would represent a later 

 phase in development than that of the n>Tnph wdth long wing 

 pads. 



3. The njTiiph with short wing pads. The frontal gland of 

 this nymph is similar in all respects except size to that of the 

 nymph with long wing pads. Although this gland as a whole is 

 smaller (fig. 6, A), its component epitheUal cells are similar in 

 height and width to those of the gland just ascribed. The two 

 types of cells, the numerous long slender ones, 1, and the few 

 swollen gland (?) cells, 2, are also present. No cuticula is dis- 



Fig. 6 Sections of the frontal gland. ^1, the median part of the ghind of a 

 nymph with short wing pads; li, the lateral part of the gland of a soldier, Homog. 

 immers. 1.8 mm., oc. 6, reduced one fifth. 



tinguishable on these cells and there is no external opening. 

 This gland is evidently not yet functional. 



4. The soldier. The cells of the elongated frontal gland of the 

 soldier form a continuous sj'ncytium, a part of which is shown 

 in section in figure 6, B. The syncytium rests upon a thin base- 

 ment membrane, the nuclei are rather widely separated, and the 

 distal, inner, surface is bordered by a wavy glassy and porous 

 cuticula. The entire inner surface is thrown into folds but the 

 average height of the component cells is lower in the soldier than 

 in the nymplis. The cells are all of one kind, and are evi- 

 dently glandular in function, the abundant cytoplasm contain- 



