Referring to the inferior jaw of a wild boar in which there was, at the extreme posterior portion, a fully-formed molar tooth which had not yet erupted, and consequently, had not any of its cusps in the slightest degree worn down by mastication, he (Dr. Shaw) said that he had read a paper some years since before the Manchester Microscopical Society, in which he had vaguely hinted at a theory which he had not since had time to work out, but which he would now distinctly state and leave it to younger men to consider. Mr. Hooton had also exhibited a most interesting specimen of a young, partly-formed and unerupted horse tooth in which also there had not been any wearing down of the cusps. He (Dr. Shaw) had several specimens of the same sort. Now, this molar horse tooth was in reality a combination of five teeth with projecting cones of various heights. As soon as the tooth appeared in the mouth these cones began to be worn down in mastication, and the tooth eventually presented a flat surface with alternate layers of enamel, dentine and cementum, so arranged that the occlusion formed a veritable mill for grinding the food. Although the molars of the bear and boar are not made up in the same way as those of the horse, the wearing down can be seen to have taken place in the teeth of the bear and the boar exhibited; and if gentlemen will kindly examine this unerupted tooth at the extreme posterior portion of the inferior jaw of the boar, it will be seen what this animal's molars are like when first formed, and before they are put to any use. _They are ummistakably made up of a great number of cones._ Therefore, it was his (Dr. Shaw's) opinion that, while in the primitive manner dentine and eventually teeth first appeared there were no signs of cones, when this form did, in the long process of time, make its appearance, it became a starting point from which has been derived, by a great variety of combinations, the forms of the teeth of the higher animals. THE TACOMA DENTAL SOCIETY. We are in receipt of a copy of the constitution and by-laws of the above Society, which indicates that the dentists of the new State of Washington are abreast of the times. “The object of this Society shall be to cultivate the science and art of dentistry, to promote among dentists mutual improvement, social intercourse and good feeling, and to collectively represent and have cognizance of the common interests of the dental profession in our city.” We take pleasure in giving to our readers the code of ethics of this new Society as being something new and original. CODE OF ETHICS. The members of the Tacoma Dental Society in the fulfillment of their duties to the profession, to the public and to each other, declare and accept as binding the following code of ethics as embracing such principles of honor, fairness and gentlemanly bearing as every gentleman of honor and self-respect should most willingly adopt. ARTICLE I.