The instances of absence of the funiculus umbilicalis, recorded by ancient writers, must evidently, as Meckel has pointed out, be considered as cases of extreme shortness of the cord. The subject is of considerable importance on account of its influence upon arrest of development, particularly of the inferior half of the foetus.

The cord varies considerably in length. Davis has seen one of two, Montault of four, Meissner and myself of five inches only; whilst on the other hand, Baudelocque has noticed one of forty-six, and Heriter one of fifty-seven inches. In the Viennese Museum there is a cord attached to a large placenta, which measures fifty-four inches; and if we allow five or six inches for the distance at which it was probably severed from the navel, the whole cord must have been from fifty-nine to sixty inches in length.

The chief deviations as to the insertion of the cord are the marginal attachment, and the insertion external to the placenta into the membranes. Occasionally we notice a premature separation of the vessels, and of the two arteries; one not unfrequently is absent, and the other is then commonly a direct continuation of the abdominal aorta.

The true knots of the umbilical cord that occur in rare cases, are of importance, as they may occasion obstacles to, or a cessation of, the circulation, in consequence of the traction exerted upon them during parturition.

Irregularities in the position of the umbilical cord very frequently present themselves in the shape of circumvolutions round different parts of the foetus; if traction is exerted upon them, the circulation may be impeded in the cord, as well as in the part of the foetus which they surround.

Rupture of the umbilical cord, or of its component vessels, and especially of the vein, are of very rare occurrence. They result from extreme traction, when the cord is either too short or twisted.

Adhesions have been noticed in rare cases between the funiculus umbilicalis, and the foetus and the membranes.

The gelatinous matter of the cord is either excessive, and the latter then appears much enlarged; or it is diminished in quantity, in which case the cord is thin, flabby, and corrugated.

The umbilical vein presents varicose dilatations and contractions, the latter particularly in the vicinity of the navel. The sheath of the cord occasionally contains serous cysts.