338 ' Etia Funk Miilise. 



fibers gradually increases until the greatest circumference of the 

 acinus is reached. From this region they decrease toward the lower 

 pole over which they pass. The average fiber about a large gland 

 has a length of from 130 to 150 microns and in the region of the 

 nucleus a diameter of from 7 to 10 microns. Several fibers are re- 

 quired to complete the circuit of the gland. There is, therefore, no 

 definite arrangement of the nuclei about any given part of the acinus. 

 Seeck describes similar structures, i. e., the spindle cells, and con- 

 siders them replacement cells for the epithelium. He denies that 

 they are muscle cells. The transverse sections of the fibers appear 

 as a layer of cubical cells (Figs. 47, 51-53, 56, Gl, 62, 65, 66, 75). 

 Weiss evidently mistook this view of the fibers for epithelium. A 

 discussion of the action of the muscle-fibers will follow later. 



Epithelium. The epithelium of this type of gland consists in 

 large part of naked nuclei. They are attached to the matrix or 

 are partly sunken in the same. They are not uniformly distributed. 

 Over small areas they form a continuous pavement; over similar 

 areas they may be entirely absent (Figs. 43-47, 56, 59-66, 75). The 

 nuclei take in general one of two forms: (1) flattened, circular 

 bodies, which appear quite uniformly dense when stained (Figs. 

 44, 59), and (2) those which arch out toward the secretion and show 

 a clear area on the attached side (Figs. 45, 47, 60, 65). Mme. 

 Phisalix studied the salamander with special reference to the part 

 played by the nucleus in evolving the secretion. She describes nuclei, 

 which take the form of parachutes and states that they are actively 

 engaged in producing poison grains. The nuclei of the toad are much 

 smaller than those of the salamander. An epithelial cell, that is, 

 a nucleus sitiuitod in a small definitely limited cytoi)lasmic mass, 

 in contact with the matrix, is seldom met with in the mature gland. 

 The body of such a cell may be densely granular (Figs. 51, 52), 

 or it may appear entirely homogeneous, or with but a few granules 

 (Figs. 51, 61). One individual, collected with others at the breeding 

 season, proved an exception in that a large number of cells were 

 present. Even in this instance there was by no means a continuous 

 cellular epithelium. The cells varied greatly in size. They were 

 found in all parts of the acinus, and were here and there greatly 



