INQUIRIES INTO THE SECRETION OF SALIVA. 
575 
EXPERIMENTAL INQUIRIES INTO THE SECRETION OF 
SALIVA. 
By M. G. Colin, Chef de Service of Anatomy at Alfort. 
M. Colin has addressed a Paper on the above subject to 
the Academy of Sciences, coming to the following con¬ 
clusions :— 
1. The divers salivary glands of solipedes act in concert 
during mastication, notwithstanding each has a special 
activity which is put in operation, and modified by certain in¬ 
fluences, 
2. The parotids secrete unequally in a given time, notwith¬ 
standing both appear under identical conditions. They 
alternate one with the other. That on the side on which 
mastication is performing produces, at least, a third more 
than its fellow; though ordinarily its product amounts to 
double or triple the quantity of the other glands 5 secretion. 
3. At the time that mastication is transferred from one 
side of the jaws to the other, there occurs a corresponding 
change in the parotid secretion. 
4. The alternations of acceleration and retardation in the 
action of the parotids succeed each other in the order of the 
changes which happen in mastication. And they are as 
observable when such changes follow each other at intervals 
of a few minutes as of half-hours or hours. 
5. These irregular alternations in the secretion are so de¬ 
pendent on the action of the parotids, that they are mani¬ 
fest even while the secretion is going on during feeding times. 
6. The secretion of the maxillary glands is differently 
regulated from that of the parotids, that of the former being 
uniform, without being influenced by mastication. 
7. The amount of saliva discharged into the mouth by 
all the glands put together, is on an average from five to six 
kilogrammes* an hour, at the time the animal is feeding on 
dry forage; when on grain, this becomes augmented a third, 
or a fourth; but is reduced to a fifth or a fourth, while the 
animal is feeding on roots. 
8. The parotids furnish upwards of two thirds of this 
amount; the maxillaries not above a twentieth. The sub- 
linguals and the molar and buccal glands the remainder. 
This proportion does not accord with the respective weights 
of the glands. 
9. The secretions of the parotid and maxillary glands is 
* A kilogramme being 2 lbs. 3 oz. and upwards, avoirdupois weight, this looks 
like a lapsus penna. 
