304 The Philippine Journal of Science 1921 
Before taking up these diseases in detail, it will be well to 
discuss their pathology and it must be freely conceded that in 
the majority of cases filarise will not be found in the peripheral 
blood. Probably this is due to one of two causes : either to the 
death of the parasite or to the blocking of the lymphatics drain- 
ing any affected area, so that the filarise cannot make their way 
into the blood. The solid oedema characterizing the disease is 
brought about not by the mere obstruction of the lymphatics, but 
by a combination of this with inflammation set up in the blocked 
area. But what causes the blockage? First there is the action 
of the parent worm, which, from injury or some other cause, 
may abort. The ova then either block the lymphatics or obstruct 
the glands of the area in question, producing a lymph stasis. 
In this area, already in a condition of lymph stasis, inflammation 
takes place, and an abscess may form which destroys the lym- 
phatics in its vicinity. Probably this plays a much greater 
part in the production of elephantiasis scroti than is supposed, 
and it is the common thing in Fukien to be able to elicit from 
elephantiasis patients a history of abscess in the scrotum, often 
the first sign of trouble in that part. To this are superadded 
frequent attacks of erysipelatoid inflammation, each attack aiding 
in the production of the permanently thickened condition of 
the tissues. In the case of the scrotum it will be observed that 
the tumor increases in size very slowly, up to a certain point, 
and then increases at a much more rapid rate. This phenom- 
enon is due to the accident of position. As long as the scrotal 
tissues are able to support the weight, the tumor remains braced 
up, so to speak. As soon as the tumor reaches a certain size, 
the tissues yield and relax. The weight of the tumor then comes 
into play, and all the lymphatics passing over the upper edge 
of the pubis are further obstructed. 
In the case of the leg, the dependent position of the part 
plays no small share in the production of the enlargement, and 
in an operation case of my own the forced rest involved by the 
operation for elephantiasis scroti sufficed to reduce the leg tem- 
porarily to a third of its former size. When one cuts into an 
elephantoid mass such as is found in elephantiasis scroti, after 
traversing the greatly hypertrophied skin, the subdermal tissues 
are found to be also much thickened, and the dilated lymphatics 
are easily made out; below this again is a mass of blubbery 
tissue containing much fluid, and this is easily traversed by the 
finger. 
