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706 lymphatics, with or without lymphorrhagia. It may happen that the obstruction is in some lymphatic tract on the distal side of the entrance of the chyle-bearing vessels into the receptaculum chyli. In this case a rupture of the consequent lymphatic varix will give issue to lymph unmixed with chyle.

Filariœ may disappear from the blood in such cases.— In filarial disease associated with lymphatic varix, micronlariae are generally present in the blood as well as in the contents of the dilated vessels. Sometimes, it is true, the microfilarise are not found. Such cases are probably of long standing; had the microfilaria been looked for at an earlier stage of the disease, it would probably have been discovered. I have watched cases in which the larva has disappeared in this way; though at first found in abundance in the blood, after a year or longer it ceased to appear there. The reason for this disappearance is doubtless the death of the parent parasites, an occurrence I have seen associated with attacks of acute lymphangitis. Although the original cause of the varix may thus disappear, the effect is permanent.

Pathology of elephantiasis arabum. Microfilariœ not usually present in the blood in elephantiasis.— In those cases of filarial disease in which elephantiasis arabum is the leading feature, it is not usual at any stage of the established disease to find microfilarise in the blood or elsewhere, unless it be in countries in which filariasis is extremely common and reinfection, or extensive infection, highly probable.

Reasons for regarding elephantiasis as a filarial disease.— From this circumstance the absence of microfilarise from the blood in elephantiasis— the question naturally arises, Why attribute this disease to the filaria? The answer to this is: (1) The geographical distribution of Filaria bancrofti and of elephantiasis arabum corresponds; where elephantiasis abounds there the filaria abounds, and vice versa. (2) Filarial lymphatic varix and elephantiasis occur in the same districts, and frequently concur in the same individual. (3) Lymph scrotum, an unquestionably filarial disease, often terminates in elephantiasis of