TREMATODA 23 



more guests remained. Somewhat improved in general health, 

 the missionary resolved to go back to his duties in China. I 

 expressed my fears, however, that his strength would prove 

 unequal to the work. 



From the size and almost leathery texture of the two flukes 

 which were in the first instance submitted to my notice, I at 

 once recognised the species ; but as they were spirit- specimens, 

 I requested that if any more examples were obtained they 

 should be sent to me in the fresh state. Fortunately others 

 were brought in a few days, when, from an examination 

 conducted whilst they were still fresh, I was able to make out 

 several details of structure which had hitherto escaped notice. 

 Altogether I secured seven specimens, three of them being in a 

 mutilated condition. In what way these mutilations (as shown 

 by my dried specimens) occurred I have not been able to make 

 out, either by personal observation or by questioning the 

 bearers. Two of the parasites look as though portions had 

 been carefully excised near the centre. The new facts I have 

 gleaned were derived from the examination of two compara- 

 tively small specimens, one of which, dried, has, by Prof, 

 Rolleston's desire, been deposited in the anatomical department 

 of the University Museum at Oxford. When I took occasion 

 to bring some of the new specimens under Mr Busk's attention, 

 he at once recognised them as referable to the species he had 

 long ago discovered. 



The earliest literary notice of Distoma crassum appeared in 

 Dr Budd's classical treatise ( On Diseases of the Liver / and in 

 it the author correctly stated, from data supplied by Mr Busk, 

 that these human flukes were "much thicker an4 larger than 

 those of the sheep/' being, it is added, from "an inch and a 

 half to near three inches in length." The longest of my recent 

 specimens, however, scarcely exceeds two inches, whilst the 

 smallest and most perfect (the one at Oxford) measures less 

 than an inch from head to tail. The greatest width of my 

 broadest specimen is little more than half an inch, or ^". 

 None of the twelve examples that I have examined approach 

 the length of three inches; but Mr Busk assured me that, 

 judging from his recollection, some of his specimens were even 

 longer than that. I fear, nevertheless, that the estimate given 

 in my Synopsis is somewhat exaggerated ; at all events it is so 

 for average specimens. 



The new anatomical facts made out by me bear reference 



