A variety of confusing terms have been used to designate the different forms of endometritis. There seem to be two chief forms of the disease: I. Chronic interstitial endometritis; II. Chronic glandular endometritis. In the first form of the disease the interglandular tissue is chiefly involved. The spaces between the glands are infiltrated with connective-tissue cells. In the second or glandular form of endometritis the disease affects the glandular apparatus. The utricular glands become much elongated, branched, and increased in number. The accompanying illustrations (Figs. 117, 118) show the microscopic appearance of interstitial endometritis and glandular endometritis. These two forms of endometritis are often mixed, and the same uterus may present the glandular form of inflammation upon part of the endometrium, the interstitial form upon another part, and the mixed form upon still another part. The gross appearance of the endometrium varies with the form of the disease and its duration. It will be remembered that in the mature uterus, in the menstrual interval, the mucous membrane is a thin reddish-gray structure about 1 millimeter (1/25 inch) in thickness. In the different forms of endometritis the mucous membrane may become hypertrophied to three or four times this thickness. In some unusual cases the mucous membrane may become even still further hypertrophied, attaining a thickness of half an inch. A special name, _fungous endometritis_, has been given to the disease when it assumes this form. Microscopic examination shows that fungous endometritis is merely a mixed form of the glandular and the interstitial varieties, with a great increase of all the elements of the mucous membrane. In fungous endometritis the hypertrophy of the mucous membrane may be uniform throughout the body of the uterus or it may occur only in localized areas. [Illustration: FIG. 117.--Interstitial endometritis: microscopic section of endometrium removed by the curette (Beyea).] [Illustration: FIG. 118.--Glandular endometritis: microscopic section of endometrium removed by the curette (Beyea).] [Illustration: FIG. 119.--Polypoid endometritis (Beyea).] In some cases the glandular hypertrophy of the mucous membrane assumes the form of polypoid growths projecting into the uterine cavity (Fig. 119). In the advanced stages of all the forms of endometritis cicatricial formation takes place. The normal ciliated epithelium of the endometrium is cast off, and is replaced by flat squamous cells. The glands atrophy; the glandular openings become dilated, and ultimately appear as simple depressions on the surface. In time secretion from the glands ceases, and the cavity of the uterus becomes lined with simple connective tissue.