certificate from the commissioner. of education of this state, showing that before entering a dental college he or she had obtained an academic education consisting of a fouryear course of study in an approved public or private high school, or the equivalent thereof." In accordance with this law the secretary will issue application blanks only upon presentation of the required certificate from the commissioner of education, Statehouse, Trenton, N. J.

Applications must be filed complete ten days before the date of the examinations. Address all communications for further particulars to

JOHN C. FORSYTH, Sec'y, 430 E. State st., Trenton N. J.

Indiana Board of Examiners. THE next meeting of the Indiana State Board of Dental Examiners will be held at the State-house, Indianapolis, June 17 to 22 inclusive. Applications and other information may be obtained by addressing

H. C. MCKITTRICK, Sec'y.
Indianapolis, Ind.

South Carolina Board of Examiners.

THE annual meeting of the South Carolina Board of Dental Examiners will be held at The Jefferson, Columbia, S. C., beginning promptly at 9 o'clock, Monday morning, June 24, 1918.

All applications must be in the hands of the secretary by June 14th. Application blanks and full information may be obtained by addressing R. L. SPENCER, Sec'y, Bennettsville, S. C.

Mississippi Board of Examiners. THE Mississippi Board of Dental Examiners will hold its next annual meeting at the State Capitol building in Jackson, on the third Tuesday in June 1918, at 8 A.M. Fee for examination $10. Practical and written examinations. Diploma from recognized

school and certificate of moral character required. No reciprocity or interchange. For further information, address

B. J. MARSHALL, Sec'y,
Marks, Miss.

F

OR some time past it has been known that human saliva is endowed with biochemical properties other than the mere saccharification of cooked starch into maltose by its amylase content, and that these facts strongly point to the possible presence of other ferments.

An analysis of the salivary glands of the ox by Rosell revealed the presence of five intracellular ferments, i.e. amylase, aldehydase, indo-phenol oxydase, catalase, and trypsin. The writer has made numerous attempts to isolate and if possible disclose the dynamics of the various ferments present in human saliva, and he succeeded in definitely verifying the existence of amylase, maltase, catalase, and oxydase. To detect trypsin, which is claimed by some investigators to be present in human saliva, the very sensitive casein-acetic acid reaction of Michaelis was applied, but not even the

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minutest trace of this ferment could be revealed.

Ferments, according to Abderhalden, may, in general, be divided into two main groups, viz, the hydrolytic and the oxidizing ferments. The former may be further subdivided according to the material to be attacked, into (a) ferments which effect the decomposition of the carbohydrates, i.e. carbohydrases, (b) the proteolytic ferments which act upon the proteins, i.e. proteases, and (c) the fatsplitting ferments, i.e. lipases.

According to the above grouping, the ferments of human saliva are represented by the carbohydrase group of the hydrolytic enzymes and by oxidizing ferments. Proteolytic and fat-splitting ferments so far have not been observed in the normal secretions of the oral cavity. Amylase, and to a much less extent maltase, are the principal carbohydrases, while oxy

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dase and catalase typify the oxidizing ferments of human saliva. The representatives of this latter group are accredited with being the oxygen-carriers

of the living tissue cell, that is, are catalytic agents which by their mere presence, even in the very minute quantities and without losing their identity, cause an indefinite amount of oxidation. These ferments are known as oxydases. The resultant peroxids of the oxydase activities are, in turn, acted upon by an additional group of ferments which by their catalytic properties reduce these peroxids with the evolution of oxygen. They are known as catalases.

The properties and dynamics of amylase have been discussed in previous papers (see DENTAL COSMOS issues for February and March). Maltase, sometimes referred to as glucodase, is a ferment which is widely distributed in the animal and vegetable kingdoms. From animal tissues it has been isolated from the salivary glands, the liver, the pancreas, etc., while in the vegetable kingdom malt and yeast are extremely rich in this enzyme. The principal function of maltase consists in splitting one molecule of maltose into two molecules of glucose.

In human saliva, very small quantities of maltase usually accompany the amylase, as was first pointed out by Von Mering. Neilson and Sheele contend that the rise and fall of the amylase index is proportionally shared by that of the maltase index. There seems to exist

close interdependence between the quantities of the various ferments, which as we have observed is apparently participated in by all the salivary ferments.

As we have mentioned above, the process of oxidation and reduction as occurring in the living cells depends upon the presence of substances which combine loosely the free oxygen at a comparatively low temperature, and which are capable of giving off their oxygen to dioxidizable substances, such as our foodstuffs. These agents are ferments, and as they are capable of changing their function repeatedly, they are referred to as reversible enzymes. As a matter of