TREMATODA 21 



observe that, in addition to the above-mentioned specimens, 

 two others are preserved in the Museum at King's College. Thus, 

 only five out of the fourteen specimens are still in existence. 



No well-authenticated second instance of the occurrence of 

 this worm took place until the year 1873, when a missionary 

 and his wife from China consulted Dr Greorge Johnson re- 

 specting parasites from which they were suffering. After a 

 brief interval, both of Dr Johnson's patients were by an act of 

 courtesy on the part of this eminent physician placed under my 

 professional care. I need hardly add that Dr Johnson had 

 from the very first recognised the trematode character of the 

 parasites. From the patients themselves I ascertained that 

 they had been resident in China for about four years. During 

 that period they had together freely partaken of fresh vege- 

 tables in the form of salad, and also occasionally of oysters, but 

 more particularly of fish, which, in common with the oysters, 

 abound in the neighbourhood of Ningpo. From their state- 

 ments it appeared to me that to one or other of these sources 

 we must look for an explanation of the fact of their concurrent 

 infection. Fluke larvge, as we know, abound in mollusks and 

 fish ; but whether any of the forms hitherto found in oysters or 

 in fish have any genetic relation to the flukes of man, is a ques- 

 tion that cannot very well be settled in the absence of direct 

 experimental proof. I should add that it was not until after 

 their visit to the interior of the country, some 130 miles distant 

 from Ningpo, that the symptoms (which Dr Johnson in the first 

 instance, and myself subsequently, considered to have been due 

 to the presence of the parasites) made their appearance. Whilst 

 in the country the missionary and his wife freely partook of 

 freshwater fish, and on one occasion they received a quantity of 

 oysters that had been sent up from Ningpo. The husband 

 assured me that the fish were always thoroughly well cooked. 



If it be asked what were the symptoms produced, I can only 

 furnish such few and hitherto unpublished particulars as the 

 missionary himself supplied. I need hardly say that he was a 

 highly cultured and intelligent gentleman, since only such 

 persons are chosen for missionary work in China. 



From inquiries made by me on the 29th of January, 1575, I 

 learnt that they left Ningpo in November, 1872, and travelled 

 thence 130 miles into the interior of the country. In the 

 following September, or about ten months subsequently, the 

 missionary was attacked with diarrhoea, which persisted until 



