156 DR. E. KLEIN. 



beculre of fibrous tissue running in various directions^ are seen 

 cut under various angles. Between these groups are the inter- 

 fascicular spaces more or less distinct and wide^ according to the 

 state of hardening, to the nature of the hardening reagent, and 

 especially to the state of the tissue itself. In a gland in which 

 oedema had been present (see Heidenhain, 1. c), even the indi- 

 vidual bundles constituting the trabeculae are separated from one 

 another by a district space ; the same may be demonstrated by 

 injecting Berlin blue into the interlobular tissue, as will be 

 described further below. In ordinary preparations hardened in 

 chromic acid or in a mixture of chromic acid and spirit, only the 

 spaces separating the groups of bundles or the trabecula3 are 

 visible, those between the individual bundles cannot be made 

 out. In preparations hardened in spirit alone, it is difficult to 

 make out in many places even the spaces between the trabeculae. 



Making a fresh preparation by teasing out the interlobular 

 connective tissue, we meet with the ordinary broader or narrower 

 bundles of fine connective-tissue fibrils and a few fine elastic 

 fibrils ; these latter may be followed for a very long course, and 

 are seen to divide, and their branchlets unite with similar ones. 

 The ordinary oval nuclei belonging to flattened connective-tissue 

 cells with finer filamentous or broader membranous processes 

 are everywhere met with. As will be described in detail below, 

 ordinary lymph-corpuscles occur in various numbers in the 

 different glands ; they are most commonly met with in the 

 sublinguahs of the guinea-pig, in the sublingualis of the dog, 

 and in some instances very numerously also in the pancreas of 

 the dog. They are of about the size of colourless blood-cor- 

 puscles, with one spherical nucleus, staining well in dyes ; the 

 substance is pale and delicately reticulated. Now and then we 

 come across a large oval or irregular-shaped cell with a spherical 

 clear nucleus and a number of bright coarse granules in the cell 

 substance — a plasma-cell of Waldeyer or a mastzelle of Ehrlich. 

 In preparations stained with logwood, these cells are very con- 

 spicuous, owing to their granules being stained a deep purple 

 colour. 



As I shall show further below, the different glands vary con- 

 siderably in this respect, i. e. in some these coarsely granular 

 plasma-cells being of frequent occurrence, in others no such 

 cells being met with. 



Making a thick section through a hardened gland, and teasing 

 out sui)erticially the interlobular connective tissue, we meet in 

 some places w^ith a section through this tissue but tilted over, 

 and we then see that the bundles of the connective tissue are 

 very densely placed against one another, and cross each other 

 in many directions, the few elnstic fibres and the plasma-cells. 



