The peritoneum is no longer regarded with awe as inviolable; by modern methods, if not as manageable as other lymphatic sacs, it is at any rate accessible enough without considerable risk to life.
Nearly all the lymphatic glands in the body are a little swollen, but the lymphatic vessels show little or no change.
From the fact that bacilli are hardly ever found in the blood of bubonic cases it may be inferred that they are arrested by the lymphatic glands next above the seat of inoculation, and that the fight - which is the illness - takes place largely in the bubo; in non-bubonic cases they are not so arrested, and the fight takes place in the general circulatory system, or in the lungs.
The lymphatic glands are hardly affected.
A characteristic feature of cancer is the carrying of the epithelial cells (which are the essential element of the growth) to the nearest lymphatic glands, and in cancer of the stomach the secondary implication of the glands may cause the formation of large masses between the stomach and the liver, which may press upon the large veins and give rise to dropsy.
In the vast majority of cases the bacilli are in the lymphatic or the circulatory system, and aerial convection, even for a short distance, seems highly improbable.
In other cases very serious disorders of the lymphatic system are brought about, of which the most marked is perhaps Elephantiasis.
This state of affairs has no antecedent improbability about it, since in the Vertebrata the coelom is unquestionably confluent with the haemal system through the lymphatic vessels.
Bancrofti is known to live in the lymphatic glands, and its embryos Microfilaria sanguinis hominis nocturna, passing by the thoracic duct, reach the blood-vessels and circulate in the blood.
Nearly all the lymphatic glands in the body are involved, and have a characteristic appearance.