( '//. INGES D URING SE CRE TIO X. 485 
general convulsions ; he considers that the saliva obtained in the 
curarised animal is due to an irradiation of nervous impulses, and not to 
a localised cortical stimulation. 
Kiilz l obtained no secretion from the submaxillary gland in unansesthet- 
ised dogs on stimulating the facial area, unless there was general tetanus, a 
condition in which Braun - had already observed a flow of saliva from the 
mouth. Lrpine and Bochef ontaine 3 obtained secretion in curarised dogs by 
stimulating the anterior portion of the cortex, including the facial area. The 
secretion was more abundant on the side stimulated. Bochefontaine, 4 shortly 
after, gave a more detailed account of the parts of the cortex from which 
secretion could be induced ; secretion was obtained by stimulating spots on the 
posterior part of the brain, and also by stimulating parts of the dura mater. 
The experiments show little or nothing as regards the question whether there 
are special areas in the cortex connected with the secretion. 
Bechterew and Mislawsky 5 found, also on curarised dogs, that the region 
which caused secretion when stimulated with weak c\irrents was more limited 
than that described by Bochefontaine. Stimulation of the anterior Sylvian and 
anterior composite convolutions caused secretion from both the submaxillary 
and parotid glands. Stimulation of the anterior limb of the sigmoid gyrus, 
and of the anterior extremities of the coronal and anterior ecto-Sylvian con- 
volutions, caused secretion from the submaxillary gland only. With stronger 
currents, secretion was sometimes obtained from the more posterior portions of 
the cortex. They found, unlike Lepine and Bochefontaine, no effect on 
stimulating the orbital convolution. 
Changes in Salivaey Glands during Secretion. 
The changes which occur in salivary glands during secretion are 
progressive, and there is no sufficient reason for believing that the 
changes which occur in the cells at the end of a day's active secretion 
differ in kind from those which occur in the first ten minutes. 
The evidence is, it seems to me, decisively against the view that 
during salivary secretion there is a breaking down of the mucous or of 
other gland cells. 6 If saliva at any stage of secretion is allowed to run 
into alcohol, mercuric chloride, or other hardening reagent, disinte- 
grating cells are not seen in the sediment as it forms, nor nuclei beyond 
those which arise from the separated cells of Wharton's duct and from 
leucocytes. And in the gland itself there is at no stage any sign of 
active cell division ; the nuclei undergoing mitotic division are as rare 
as they are in the resting gland. 7 
Two fundamental changes undoubtedly take place in the gland cells 
during secretion. 
There is, first, an excretion of a greater or less amount of the sub- 
stance which has been previously formed in the cells; 8 this substance, 
1 Centralbl. f. d. med. JFisscnsch., Berlin, 1875, S. 419. 
2 Beitr. z. Anat. u, Physiol. (Eckhard), Giessen, 1876, Bd. vii. S. 136. 
3 Gaz. mid. de Paris, 1875, p. 332. 
4 Arch, de physiol. norm, etpath., Paris, 1876, p. 161. 
5 Neurol. Centralbl., Leipzig, 1888, p. 553. 
6 It must be mentioned, however, that Heidenhain in his treatise (Hermann's 
"Handbuch," 1890, Bd. v.) maintains the view originally advanced by him, that mucous 
cells disintegrate to form part of the secretion. 
7 Langley, Proc. Roy. Soc. London, 1886, vol. xli. p. 362 ; Bizzozero, Firchow's Archiv, 
1887, Bd. ex. S. 181. 
8 Heidenhain, Arch. f. d. ges. Physiol. Bonn. 1S78, Bd. xvii. S. 43; Hermann's 
"Handbuch," 1883 ; Lavdowsky, Arch. f. mikr. Anat., Bonn, 1877, Bd. xiii. S. 335. 
