Rarely, I am bound to admit, is the field of all of these operations as distinctly limited in practice as is here indicated, and one, perhaps two, are rarely selected. Thyro-cricotomy (old term laryngotomy) is often indicated, and cricotomy and median tracheotomy are sometimes performed as here described. Superior tracheotomy is commonly a combination of at least two of the methods--viz. the division of the upper rings of the trachea and the cricoid cartilage as well. It may even, probably frequently does, trench also upon the thyro-cricoid membrane (thyro-cricotomy) and upon the field of a median tracheotomy, the isthmus being pushed downward or even cut or torn through. The latter operation and cricotomy are, I believe, rarely if ever done from choice. Finally, inferior tracheotomy is a common method. As here described, it meets a large number of indications, and, despite its superior difficulties over the higher operations, is therefore necessarily often chosen; not infrequently, however, does it invade the median region, the isthmus of the thyroid being pushed upward. Which of these operations shall be selected in a given case depends upon the particular conditions which render it necessary, and likewise, to some extent, upon the age of the patient. Durham summarizes the question very fairly. Thyro-cricotomy (old term laryngotomy) is by far the easiest operation to perform, and its execution is attended by least risk; therefore it is the operation to be preferred in any sudden emergency when suffocation threatens, and especially where the surgeon is alone with the patient. Generally, it is not as applicable as the others, especially in early childhood, on account of the limited dimensions of the thyro-cricoid space. It cannot be recommended in cases of acute or extensive diseases or injuries of the larynx, nor is it likely to be of much service if a foreign body is in the trachea or bronchus. On the other hand, it is probably the best operation to adopt in cases in which foreign bodies are impacted in the larynx, in cases of limited chronic disease or contractions of the superior laryngeal parts--usually the result of syphilitic ulceration--and in cases in which respiration is impeded by intra-laryngeal growths which cannot be removed by the natural passages. Cricotomy, combined with superior tracheotomy (old term laryngo-tracheotomy), is not a difficult operation, and may be advantageously practised, especially in children; in the adult it meets many indications. Holmes recommends it the more urgently, in preference to an inferior tracheotomy, the earlier the age of the subject may be.