To this pericardial coelom is frequently added a gonocoel enclosing the gonads and the funnels of their ducts.
The walls of the pericardium are also excretory in parts, these parts forming the pericardial glands.
The its muscular coat; g, g, the heart is of the usual Arthro lateral teeth, which when podous type, lying in a more or in use are brought in conless well-defined pericardial blood tact with the sides of the sinus, with which it communi median tooth m; c, c, the cates by valvular openings or muscular coat.
When the pericardium is cut open from above in an animal otherwise entire, the anterior face of the kidney is seen forming the posterior wall of the pericardial chamber; on the deep edge of this face, a little to the left of the attachment of the auricle to the floor of the pericardium, is seen a depression; this depression contains the opening from the pericardium into the kidney.
By the pulsation of the pericardial vesicle (best observed in the larva) the blood is driven into the glomerulus, from which it issues by efferent vessels which effect a junction with the ventral (sub-intestinal) vessel in the trunk.