Royal Microscojncal Society. 247 



the outer border or boundary was noticed to be formed chiefly of 

 altered fibrous tissue very much cretified, yet otherwise structureless, 

 and between these was seen very distinct fibrous and connective 

 tissue free of cretaceous particles. Some free ova were also seen. 

 Seeing these particulars, naturally awakened considerable interest ; 

 but being otherwise much occupied at the time, the encysted body 

 was flushed with water, and put aside in a mixture of weak gly- 

 cerine and saturated solution of the acetate of potash, for future 

 further examination. 



It remained in this solution for some days, when I had the 

 opportunity of showing it to my friend Dr. Aitken, Professor of 

 Pathology of the Koyal Victoria Hospital, Netley, who at once, 

 from his extended knowledge of these subjects, recognized the 

 novelty of the example of an encysted parasite yet furnished with 

 ova. Later it became a question as to the best method of seeking 

 for the entozoon which had furnished these particulars. 



Taking the encysted body between the fingers to make fresh 

 sections it slipped as if non-attached from the fibroid capsule, and 

 was found too soft to furnish successful sections ; hence I com- 

 menced, under a hand-lens, tryiDg to remove the parasite from the 

 central cavity, but finding it break away in small portions, these 

 were taken up on a flattened curved needle, and placed on several 

 slides with a little glycerine, temporarily covered from dust, until 

 the whole was removed. The cavity was now seen to be narrow 

 yet broad, or sole-shaped, and the section had been carried longi- 

 tudinally through the narrow axis. Small portions from the slides 

 were removed by needles to another slide with glycerine, and covered 

 with a thin cover. Thus the whole was examined very carefully at 

 the magnification of 160 diameters. The first part found of chi- 

 tinous structure, was the small peculiarly-constructed plate, repre- 

 sented in Fig. 4, and of which only one was seen. To what part of 

 the parasite this may belong is to me quite unknown, though it is 

 suspected to have been from one of the suckers. Continuing the 

 examination very carefully in this manner three hooks were dis- 

 covered, Fig. 5, and the shaft of a fourth; also eight small spines, 

 one barbed or bifid, Fig. 6, and numerous small denticulated frag- 

 ments of thin chitinous narrow plates, Fig. 7 ; likewise several larger 

 structureless horny plates, sharp at one edge and rather thicker at 

 the other, apparently a broken surface, Fig. 8. Having found the 

 hooks, I was anxious to learn more, if possible, of the structure of 

 the parasite. Examining some of the larger portions, they appeared 

 to form parts of the ovarium, or may be the vitelligene organ; they 

 were loaded with highly refractive so-called calcareous corpuscles 

 and immature ova ; a small portion of one of these masses is repre- 

 sented in Fig. 3. The outline of these parts on one side corresponded 

 closely before compression to the rugose or mammillated border of 



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