246 Transactions of the 



which, in household phraseology, passes by the name of " the best 

 end of the neck of mutton." 



Projecting from the cut surface of the joint, but well covered by 

 the muscular structure, was a small nodulated, yellowish-looking 

 mass, hard to the touch, and situated just in the centre of the 

 muscles of the longissimus dorsi, forming the chief fleshy part of 

 the chop. After its removal, much of the surrounding muscular 

 structure was cut away and a section made through the centre of 

 the encysted mass, exposing a small pisiform fibrous-looking body, 

 bounded externally by altered tissue containing small cretaceous 

 nodules, which gave rise to the little nodulations, whilst centrally, 

 was seen an irregularly sinuous linear-looking cavity, itself bounded 

 by a narrow band of hardened tissue, paler than the rest ; the space 

 between this, the endocyst (?) and the outer border or ectocyst(?) 

 was occupied by a more or less compact, well-marked fibrous and 

 connective tissue. These boundaries were well distinguished by the 

 differences in their colour, due apparently to the cretification which 

 had happened to the outer one, and to the amount of minute so- 

 called calcareous particles, found afterwards, in the inner one. The 

 general appearance of the cut surface of one half is given in Fig. 1, 

 twice the natural size. With a low-power hand-lens, the central 

 cavity was seen to be filled with a soft grumous-looking body, 

 retaining the figure of the boundary, apparently without any definite 

 structure, but which on one of the halves had been slightly dragged 

 above the cut surface on dividing the cyst. This little nodulated 

 mass was enclosed in a distinct capsule, formed of the altered 

 surrounding muscular structure and fibrous tissue, set up, as usual, 

 in self-defence against the extraneous body. The pisiform nodulated 

 mass appeared to be free in this capsule. The neighbouring flesh, 

 as indeed all others of the exposed parts of the joint, looked perfectly 

 healthy and sound, and had been taken from a young sheep. 



A thin section was made across one of the halves of the encysted 

 mass and placed with a little distilled water on a slide for examina- 

 tion under the microscope. Besides a quantity of grumous matter 

 and minute calcareous particles and corpuscles, the section furnished 

 a slice of free integument, bordered on one side by what I took to 

 be rugae. This is seen in Fig. 2, compressed; — a section of the 

 ovarium, or may be vitelligene organ, with immature ova and very 

 many calcareous corpuscles, Fig. 3; — portions of the endocyst, which, 

 in this case, was of some thickness, and, to some slight extent, 

 appeared as if imperfectly laminated ; but the cut edge did not curl 

 itself up, as is usual in the hydatid cyst of Taenia echinococcus, 

 though this might have been due to the quantity of fine calcareous 

 particles with which the whole boundary seemed loaded, nor could 

 any fine distinct cellular membrane, the ordinary granular layer, be 

 detected, as forming a distinct membrane to the endocyst (?), whilst 



