1889.] MICROSCOPICAL JOURNAL. 195 



We notice four distinct appearances : 



i st. Oval bodies with an outer and an inner membrane, the inner be- 

 ing the sharper and apparently the thicker. In the centre of this body 

 is a mass of granular material, irregular in outline and of a shrunken 

 appearance, occupying fully one-half the central cavity. The granular 

 material has taken the stain ; the rest of the body has not. (Fig. 3, a.) 



2d. Round bodies having the same diameter as those first noticed, 

 the same outer and inner walls and the same central granular mass. 

 (Fig- 3, *>.) 



Clearly these are the bodies first noticed, cut through their short di- 

 ameter. 



3d. Opaque, black bodies, having the same size and shape as our 

 first ones. An outer, but not an inner, membrane can be made out. 

 They reflect light, but do not polarize. 



We are warranted, I think, in the assumption that we have to deal 

 with the same bodies as before, but bodies which have undergone a de- 

 generation, most probably the calcareous one. 



4th. In some of the bodies we notice on one end, and in some on 

 both ends, short prolongations of the outer membrane which by focus- 

 ing are seen to be tubular. With the power used I , cannot say 

 whether they do or do not communicate with the central cavity. (Fig. 

 3, c.) Apparently they do. I am also uncertain as to whether or not 

 the inner membrane lines these prolongations. With the one-fifth I 

 cannot see that it does, and as I do not propose to go further than the 

 facts observed will warrant me, I shall leave this for future study with 

 higher powers. 



Looking over these four groups we see that they are but variations 

 of the same body. We also see that in this body there is no trace of 

 circulatory or nervous systems, no breathing or digestive apparatus. 

 It is evidently a cell, and it is equally evident that it is a parasite, as it 

 differs entirely from what we have seen to be the normal structure of 

 the liver. 



I am not aware of any vegetable parasite which possesses the power 

 of living and developing in a like situation, and this cell evidently has 

 lived and developed since it and its companions have replaced a con- 

 siderable amount of liver-tissue. We may assume, then, that we are 

 dealing with an animal cell. I will not stop here to enumerate the 

 characteristic qualities of the ovum. They are known to you all. I 

 will merely say that in shape and structure our unknown body fulfils 

 the requirements of an ovum in that it is oval, has an outer and inner 

 membrane, inclosing granular contents. We are dealing, therefore, 

 with ova. We know that the ova most likely to be found in the liver 

 are those of the intestinal worms. Let us, therefore, examine the in- 

 testinal parasites and their ova and see if we can find anything answer- 

 ing to what we have seen. And here we must leave bur microscope 

 and accept facts observed and noted by others. Any helminthologist 

 would go at once to Leuckart and Cobbold. Let us follow his example. 



Among the Nematode worms of the family Filaridse we find one, Tri- 

 chocephalus dzspar, the ova of which are described as having a longi- 

 tudinal diameter of from ^ w inch to -^-$ inch and having at each end 

 a protrusion in the form of a papilla. Embryos are scarcely or never 

 seen. Some authors describe and figure the protuberance as composed 



