﻿36 MUSGRAVE. 



mature specimens, but in many instances this is indistinct and at times 

 it can not be made out at all. This operculum has quite a distinctive 

 appearance which is noticeably different from that of some of the other 

 fluke eggs. The operculum in the ova under consideration appears to 

 fit into an opening very much in the manner of a cork into a bottle, 

 whereas in some of the other trematodes, particularly Opisthorcliis, the 

 opercula appear to be placed over openings more in the fashion of a cap. 

 The ovic cell in many specimens is quite distinct, and several yolk cells 

 are then also present, but in others, even if they are taken from the 

 same abscess, no such structure can be made out. 



(c) Life cycle. — The life cycle of this worm is unknown; this fact is 

 brought out by Table No. 3. When the eggs are oviposited they do not 

 contain an embryo, but Manson and a few other observers have succeeded 

 in hatching free swimming, ciliated miracidia from these eggs by placing 

 them in water for given lengths of time. I have repeated these experi- 

 ments many times, but so far have not succeeded in obtaining the mira- 

 cidia. The sporocyst, redia, cercaria and intermediate host or hosts are 

 absolutely unknown, but reasoning from analogy it is probable that the 

 intermediate host will be found to be some form of edible snail. 



(d) Habitat. — The habitat is in man (all tissues and organs) the 

 dog, cat, hog, cow and tiger. In the Philippine Islands it has been found 

 in man and the cat. The men under my observation were one Chinaman 

 and two Japanese, the others being native Filipinos. Thirty-two autopsies 

 on cats were performed and although fluke infections were present in over 

 60 per cent of the animals, P. westermanii was found but once. It has 

 not been encountered, even after careful search in rats, dogs, or monkeys. 



(e) Distribution in the body. — The parasites or eggs have been re- 

 ported according to previous literature in the following places : The lung, 

 brain, eyelids, liver, intestinal wall, omentum, diaphragm, cervical glands, 

 in Poupart's ligament, the perineum, appendix, rectum, peritoneum, cir- 

 rhotic liver, and free in the abdominal cavity. 



Looss and other careful workers doubt the diagnosis in some of these 

 cases. However that may be, I now wish to confirm every one of the 

 above-mentioned sites of infection and to acid to them practically every 

 other tissue and organ in the body. Particular attention may be called 

 to the spleen, skin (ulcers), lymphatics, pancreas, heart and pericar- 

 dium, the epididymis, urinary bladder, psoas and other muscles, and 

 many other places. In fact, in some of my cases which have been de- 

 scribed above the distribution of the parasites, eggs and lesions was 

 sufficiently universal to justify the term of general infection. 



(f) Primary points of infection and manner of spread in the body.- — 

 The exact mode of infection can not, of course, be determined until the 



