"The affection often commences in one of the thyroid glands, which slowly but gradually increases in size, feels firm when grasped, and evinces very little tenderness. Generally the attendant is alarmed by a snoring or wheezing noise emitted by the animal in respiration, before he is aware of the existence of any tumefaction. This continues to increase, embracing in its progress the adjacent cellular and muscular tissues, and frequently the submaxillary and parotid glands. It becomes firmly attached to the skin through which an opening is ultimately effected by the pressure of pus from the centre of the tumor. "The swelling often presents an irregular surface, and various centres of maturation exist; but the evacuations only effect a partial and temporary reduction of its bulk, in consequence of the continued extension of the morbid growth and ulcerative process which often proceed towards the pharynx, rendering respiration and deglutition still more difficult, until at length the animal sinks from atrophy or _phthisis pulmonalis_. "In the early part of my practice, having been frustrated in my attempts to establish healthy action in these ulcers, and referring to the works that I had on surgery for information, I concluded that they bore some resemblance to cancer in the human being, and determined to attempt extirpation. Subsequently, numerous cases have occurred in which I have successfully carried that determination into effect. I have had some instances of failure, which failure always arose from some portion of the morbid growth having been left. "In the first stage, I have reason to believe that the tumor may be dispersed by the general and topical use of the iodurets. After the suppuration, I have tried them in vain. "As soon as the nature of the tumor is clearly developed, I generally attempt its removal, and, when most prominent by the side of the larynx, I proceed in the following manner:--Having cast the beast, turned the occiput toward the ground, and bolstered it up with bundles of straw, I proceed to make an incision through it, if the skin is free, parallel with, and over, and between the trachea and _sterno-maxillaris_, extending it sufficiently forward into the inter-maxillary spaces. If I find it firmly attached to the apex of the tumor, I then enclose it in a curvilinear incision and proceed to detach the healthy skin to beyond the verge of the tumor. "Its edges being held by an assistant, the knife is directed downwards through the subcutaneous parts, and all those that exhibit the slightest change from healthy structure are removed. "By tying any considerable blood-vessel before dividing it, and by using the handle of the scalpel and the fingers in detaching the portion of the parotid gland towards the ear the hemorrhage was always inconsiderable.