There is apresented an anatomical and histological description of the salivary glands of the Triatoma infestans. Being modificated labial glands, the salivary glands represent a pair of glandular complexes each of which with three glands. Each gland is composed of a wall with an unicellular layer including a relatively spacious cavity, the so-called reservatory. The two first glands (D 1 and D 2) are situated closely togheter. Between them lies a hilus, into which enters a long canal of ligation comming from the third gland (D 3) situated more backward. By intercalation of the hilus the three excretions of the different glands are mixed automaticaly, always in the same proportion, so that the composition of the salivary liquid oscilates only in an unimportant rate. All the glands possess a muscular system on their surfaces and valves to be opened by muscles. The innervation is effected from the posterior part of the suboesophagial ganglion (labial segment of the head) by the nervus glandulae salivaris (labialis). This nerv accompanies the general salivary duct (between the hilus and the salivary pump) and is divided in three branches which run to each of the three glands. The end of the ectodermal part of the salivary sistem lies in the middle of the valves of all the three glands. The ducts and the hilus are provided with a cuticula. The cells of all the three glands possess two nuclei. Each gland shows a typical manner of excretion. Hungry animals possess almost exclusively cells in the state of regeneration or repouse. The expulsion of the excretion out of the cells is effected during or a little after the sting; the liquid enters the cavity of the gland, so that quantity of saliva, used during the sting, is compensated. There is to be observed a correlation between protoplasm and nuclei during and after the expulsion of the saliva. The opinion of HEIDENHAIN could be confirmed that the formation of the excretion is a autonomous process of the protoplasm...