236 



DISCOVERY REPORTS 



Fig. 17. a. Thin section through antennal gland of embryo showing thick walled intracellular duct, four 

 cells forming sphincter and end sac with thick walls penetrated by intracellular cavities, b. Thin section 

 through antennal gland of adult. The end sac wall has become much folded and in its crypts can be seen 

 blood cells with peculiar amoeboid processes. The duct is very thin walled — the wall is represented by the 

 thick black line only— and is covered on its inner side by gland cells, c. Thin section through sphincter. 

 d. Surface view of sphincter, b.c. blood cells ; a: crypts ramifying in end sac wall ; e.s.zv. wall of end sac ; 

 gl.c. gland cells; Leo. openings leading into intracellular crypts from the outer surface of the end sac 

 epithelium. 



