26 PARASITES OF MAN 



resident in the human liver, where its presence, moreover, 

 undoubtedly contributed towards the production of the fatal 

 result. 



In my remarks on the missionary's diet it is hinted that 

 the Ningpo oysters may have played the role of intermediary 

 bearers to the parasite in question; and as tending in some 

 measure to strengthen this notion, it should be borne in mind 

 that Mr Busk's original fluke-bearer came from the east. It 

 is not improbable that the Lascar host may have partaken of 

 the same particular species of fish or shell-fish that the 

 missionary and his wife partook of. Be that as it may, the 

 frequency of the, occurrence of Trematodes and their larvae in 

 marine mollusks is well known. According to Woodward, 

 several species of oyster- are sold in the Indian and Chinese 

 markets. Thus, it would require the skill of a malacologist to 

 deternfine the particular species of Ostrea to which the Ningpo 

 oysters should be referred. 



Mons. Giard is of opinion that the singular larvae known as 

 Bucephali attain sexual maturity in sharks and dog-fishes; 

 therefore it is extremely unlikely that the Bucephali should have 

 been in any way concerned in 'the infection of our missionary 

 and his wife ; nevertheless there remains the probability that 

 these human bearers swallowed other kinds of Trematode 

 larvae when they consumed the Ningpo oysters. Moreover, if 

 it should happen that none of the other larvae occurring in 

 oysters are capable of developing into flukes in the human 

 territory, it yet remains highly probable that some one or other 

 of the various encysted (and therefore sexually immature) 

 Trematodes known to infest marine fishes will turn out to be 

 the representative of our Distoma crassum. In this connection 

 we must not forget that the flesh of the Salmonicke forms the 

 probable source of human Bothriocephali ; and there is some 

 likelihood that salt-water fishes, if not actually the primary, 

 may become (after the manner explained by M. Giard) the 

 secondary intermediary bearers of fluke-larvae. At all events, 

 I am inclined to look to the Ningpo oysters, or to some 

 other of the various species of marine shell-fish sold in eastern 

 markets, as the direct source of Distoma crassum; for, in 

 addition to the bucephaloid cercarians, we have abundant 

 evidence of the existence of other and more highly developed 

 fluke-larvae in marine bivalve mollusks. 



In this connection I will only further observe that we possess 



