54: REPORT—1874. 
under the six heads above detailed, I hope it may be admitted that, notwith- 
standing recent progress, there is still a wide field open for the researches of 
the systematic botanist, and that his branch of the science is not the mere 
child’s play or herbarium amusement it has been charged with; for no 
thorough knowledge of plants can be satisfactorily obtained or success- 
fully communicated without scientific method, and no such method can be 
framed without a thorough study of the plants methodized in eyery point 
of view. 
Report of the Committee, consisting of Dr. Pyz-Smiru, Dr. Brunton 
_ (Secretary), and Mr. West, appointed for the purpose of investi- 
gating the Nature of Intestinal Secretion. 
For some time the opinion has prevailed among physiologists that the nervous 
system not only exerts an influence upon the calibre of the vessels supplying 
glands with blood for secretion, but that the secreting cells themselves are 
excited to action by nervous stimuli. So firmly, indeed, has this opinion been 
held, that Pfliiger’s discovery of nerves terminating in the secreting cells has 
been almost universally accepted, notwithstanding his failure to demonstrate 
these structures to others. Partly, no doubt, this belief has been due to the 
high personal consideration in which this distinguished physiologist is justly 
held, but it is also due in part to the conviction which prevails that such 
structures must exist. 
A distinct proof to this effect has been afforded by the researches of 
Heidenhain, on the effect of atropia upon the secretion of the submaxillary 
gland. 
When one of the nerves going to this gland (viz. the chorda tympani) is 
stimulated, two effects usually follow :—First, the vessels going to the gland * 
dilate, the blood flows quickly through them, and a free supply of lymph is 
poured out into the lymph-spaces surrounding the gland; secondly, the cells 
of the gland absorb this lymph, convert it into saliva, and pour it out into the 
duct of the gland. 
If the animal be partially poisoned with belladonna (or its active principle 
atropia), or if atropia be injected into the vessels of the gland itself so as to 
exert its poisonous action upon the branches of the chorda tympani ending 
in the gland, a very different result takes place. 
When the nerve is then irritated the vessels dilate as before, the blood 
pours rapidly through them, but not a drop of saliva is secreted. That part 
of the chorda tympani which acts on the vessels has not been affected by the 
poison, but those fibres which go to the secreting cells and stimulate them 
to secrete have been paralyzed by it. 
_ It is obvious, however, that the salivary secretion is only exceptionally 
induced by direct irritation of the chorda tympani nerve, lying as this does 
far below the surface and well protected from external influences. Usually . 
secretion is induced reflexly from the mucous membrane of the mouth or 
tongue, the impression made by sapid substances upon the sensory nerves of 
these parts being transmitted up to the brain and then reflected outwards 
along the chorda tympani to the gland. 
