These growths are without doubt often merely local, and curable by extirpation. In many cases, however, notwithstanding precisely the same morphological and chemical relations, they accord so entirely in all their manifestations with the cancers, that we classify them with these as a further variety of medullary carcinoma, to which in their lineaments, also, they approximate the most nearly.

Their occurrence we believe to be limited to the mucous membranes and the common integuments. We have seen them upon the mucous membrane of the larynx and trachea; of the stomach, the rectum, the urinary bladder; upon and in the common integument, and in the subcutaneous textures of the lips and face; in the scrotum, glans, and prepuce; in the external labia pudendi; upon the skin of the lower extremities. In a parenchyma we have met them but once, namely, in the liver, where they were encysted in a capsule of fibro-cellular tissue.

Upon mucous membranes these alien growths usually appear as rather thickly pedunculated, roundish, cauliflower-like, or warty, leaf-like, stella-clavate, whitish, reddish-white, purple, vascularized, sometimes tolerably firm, often flabby, very vulnerable tumors, easily rent asunder by compression. Upon the common integument they sometimes form similar, now and then tolerably voluminous, tumors. More frequently, however, the alien growth appears as a diffuse degeneration of the skin, which presents a warty, foliated surface, overgrown with luxuriating papillae, or else, under different structural relations of the new growth, a gland-like, sore, whitish-red, or red patch, which, under sloughing and offthrowing of the alien growth, degenerates into one or several ridge-bound ulcers.

A more minute examination shows these out-growths to consist altogether of cells, which have hitherto seemed to us perfectly analogous, both in themselves and in their development, with the epidermidal or the greater epithelial cells of the tessellated structure. The mature cells are often of colossal size, flattened, mostly rhomboidal, furnished with one or two oval, reddish, or yellowish-red nuclei. The younger cells are smaller, roundish, spherical, limpid, or, around the nucleus, granulated in the figure of a sharply defined areola; whilst roundish, pale-red nuclei are present at their side. The older cells are of scale-like flatness, - their nuclei indistinct, or, it may be, completely obliterated.

In ulterior development the cell does not surpass -

(a.) A lengthening in one direction, with transformation to a rhomb or to a riband-like layer terminating at both ends in a short apex.

(b.) A parent-cell, within which occurs a second generation of cells, a development indicative of an alveolar disposition in the other surrounding elements.

These elements are held together by a very scanty, imperceptible, intercellular substance, and give way under moderate pressure, or without this, under the influence of acetic acid, or of other acids which serve to dissolve the intercellular substance.

The cells themselves manifest towards acetic acid relations varying with their age, the older ones not being changed, the younger ones becoming more transparent and gradually dissolved by it, whilst the nuclei are brought more distinctly into relief. When rubbed up with water they impart to it a whitish turbidness, and the young cells lend to their laxer bond-substance an encephaloid aspect.

The secondary arrangement of these elements is very remarkable. It consists:

(a.) In their arraying themselves in warty, or warty layer-like growths.

(b.) In their arraying themselves in cylindrical or facetted fibres or cylinders, which, gathered together into fasciculi, give the new growth a fibred structure, a fibrous torn surface.

(E.) In Alveolar Order

Elongated cells of the secondary form above specified, course around circular gaps in which are impacted a brood of younger nucleated cells, either spherical, or, when very numerous, mutually compressed into polygonal shapes.

In the larynx, this formation constitutes the out-growths denominated by Albers warty, laryngeal tumors; many lax, succulent, seemingly fibrous, for the most part very sensitive, integumental, and subintegu-mental warts, a large proportion of cancers of the lip, scrotal or chimney-sweeper's cancer, a not uncommon condyloma-like degeneration of the glans penis, cancer of the external sexual organs in the female, and especially of the external labia. Many of these, more particularly cancers of the lips, have a seeming glandular texture determined by the alveolar type. From the common integument they assail subcutaneous textures without distinction, - even bone; from mucous membranes, the submucous textures: at the larynx, the arytenoid cartilages so commonly that one is induced to believe that the alien substance may in some cases originate with these.

Epidermidal cancer ulcerates, in the sequel of inflammation, in a form identical to all appearance with that of the most exquisite cancer. The base of the ulcer is invested with a yellowish-white, or a white, creamlike exudate, consisting mostly of lustrous, reddish nuclei. Lastly, to this alien growth is to be reckoned, without doubt, an ulcer developed out of a wart-like, transparent, hardish protuberance, in form thoroughly identical with ulcerating cancer, and not unfrequently seen to attack aged persons in the face. The base and edges of this ulcer consist of round, lustrous, reddish nuclei in an amorphous bond-mass, and the white, creamy exudate investing the ulcer reveals the same composition. It represents embryonic stages of epithelial cancer. Certain epidermidal cancers of the lip are similarly constituted.