The fissure is sometimes difficult to find, and must be searched for in the folds of the anus. This can be accomplished by drawing the mucous membrane away on each side, by which means we shall usually be able to see just within the orifice an elongated, club-shaped ulcer, the floor of which may be very red and inflamed, or, if the disease is of long standing, of a grayish color, with the edges well defined and indurated. Sometimes the ulcer is quite superficial, while in other instances it extends completely through the muco-cutaneous surface, exposing the subjacent muscular coat. Cripps[18] states that these ulcers are sometimes undermined, so that a probe may be passed for a short distance beneath them, while occasionally a little fistulous channel will run some distance up the anus. A fact to which special attention should be directed here is that small ulcerations may exist in the sinuses of Morgagni. Kelsey[19] and Vance[20] have met with such cases, the ulceration being completely hidden from sight, and detectable only by the sharp pain caused by the introduction of a small bent probe. This condition is no doubt a rare one, but is none the less important on this account, for its situation is such that it may be readily overlooked. The next step in the examination of a case of fissure is the introduction of the finger into the rectum,[21] and it should be conducted in the following manner.[22] If the lesion be situated dorsally, pressure should be made by the finger toward the perineum, thus avoiding the fissure and rendering the introduction of the digit as painless as possible. If the fissure be situated anteriorly or laterally, the finger should be pressed toward the opposite side of the bowel. In cases of fissure the speculum ani is seldom required by those accustomed to making rectal examinations. In the majority of instances the possession of the _tactus eruditus_—education of the sense of touch—will enable the surgeon to form a correct diagnosis without the aid of this instrument, and thus save the patient much pain. If a speculum should be required, the instrument of Aloe (Fig. 5) or of Sims (Fig. 6) may be employed. [Illustration: Fig. 5—Aloe's Speculum.] [Illustration: Fig. 6—Sims' Speculum (detachable handle).] It is not an uncommon occurrence, according to Allingham,[23] to find a polypus associated with fissure, it being situated at the upper end of the ulcer, or lying against it on the opposite side of the wall of the rectum. I have met with several such instances. If the polypus be undiscovered, treatment of the fissure will prove useless, for it will not heal until the polypoid growth is removed. In searching for a polypus, it is important to remember that the investigation should be conducted by passing the finger from above downward, as otherwise the tumor may be pushed up out of reach, the pedicle in these cases often being of considerable length.