A median mesentery running dorsoventrally supports the alimentary canal and is continued behind it into the tail, thus dividing the body cavity into two lateral halves.
Difficulty may be encountered in the thickened mesentery of patients with Crohn's disease.
Each mesentery has a filament; but two of them, namely, the pair farthest from the sulcus, are longer than the rest, and have a different form of filament.
Each mesentery is attached by its upper margin to the peristome, by its outer margin to the body-wall, and by its lower margin to the basal disk.
In the region of the mouth where the two halves of the small arm-sinus approach one another they open into a central sinus lying beneath the oesophagus and partly walled in by the two halves of the ventral mesentery.
The collarcavity (b.c. 2) is paired, although its ventral mesentery is not complete.
The intestine is slung by a median dorsal and ventral mesentery which divides the body cavity into two symmetrically shaped halves; it is " stayed " by two transverse septa, the anterior or gastroparietal band running from the stomach to the body wall and the posterior or ileoparietal band running from the intestine to the body wall.
The liver first appears as an ento dermal hollow longitudinal outgrowth from the duo denum into the ventral mesentery.
The lower part of the free edge of every mesentery, whether complete or incomplete, is thrown into numerous puckers or folds, and is furnished with a glandular thickening known as a mesenterial filament.
The postseptal coelom is partially divided by a ventral mesentery which is attached along the entire length of the convex.
The postseptal division is a coelomic space, partially subdivided by a ventral mesentery.
This vessel is nothing but a split between the right and left folds of the mesentery, and its cavity is thus a remnant of the blastocoel.