slightest injury, then elephantiasis will supervene; for, unless the lymphatics of an inflamed area are patent, the products of inflammation are not completely absorbed. Erysipelatoid inflammation, frequently recurring, is a well-recognized feature of almost every case of elephantiasis arabum.
Sequence of events in elephantiasis.— The sequence of events in the production of elephantiasis is, I believe, as follows: Parent female filaria in the lymphatic system of the affected part; obstructive fibrotic changes in the glands or lymphatic trunks; or injury of the filaria leading to premature expulsion of ova; and embolism of lymphatic glands supervening on either of these causes of obstruction; stasis of lymph; lymphangitis from subsequent traumatism or other cause (as septic infection) in the congested area; imperfect absorption of the products of inflammation; recurring attacks of inflammation leading to gradual, intermittently progressive, inflammatory hypertrophy of the part.
In this way I explain the production of elephantiasis by the filaria. And in this way I explain the absence from the blood of the larvæ of the parasite which started the disease; they cannot pass the occluded glands. Very likely the parent worm or worms die at an early stage of the disease, killed by the subsequent lymphangitis, or by the cause which led to premature parturition.
The subjects of elephantiasis less liable than others to microfilariœ in the blood.— Some years ago I made a curious observation which supports the view just stated. I received from Surgeon-Major Elcum 88 slides of night blood from 88 natives of Cochin. Of these 88 persons, 14 were affected with elephantiasis, 74 were not so affected. Of the slides coming from the 74 non-elephantiasis cases, 20 contained microfilariæ, one in every 3½; of the 14 elephantiasis cases, only 1 had microfilariae. Why should the elephantiasis cases have proportionately fewer microfilariæ than the non-elephantiasis cases? The answer may be, that in the former the existence of elephantiasis implied that a large area of their lymphatic systems
