in the Lnings of a Sheep. 103 



more opake and interspersed with numerous white specks^ while 

 the other was semitransparent and resembled soft tubercle. The 

 exterior of all the masses lay immediately underneath the serous 

 membrane, and some of them penetrated the pulmonary tissue, 

 which was otherwise healthy, for about a quarter of an inch. 



A thin section was placed beneath the microscope and examined 

 by reflected light, when a great many little objects, probably the 

 white specks just spoken of, resembling in colour and outline 

 grains of pearl barley, were seen distributed through the sur- 

 rounding tissue. But with the aid of transmitted light and 

 lenses of greater magnifying power (^-inch focus), a number of 

 animalcules, such as represented in the annexed figure (Plate \.B 

 iig. 1), were seen coiled up and imbedded in a brownish mass 

 consisting of minute cells and granules. They were very abun- 

 dant in the opake portion of the section, and were very closely 

 aggregated together in spots probably corresponding to the specks, 

 whereas in the intervening portions as well as in the surround- 

 ing more transparent structure, comparatively few were to be 

 found. On making our first observation each individual was 

 inclosed in a transparent membrane, which upon a subsequent 

 examination was proved to be the wall of the ovum. We after- 

 wards found many that had escaped from this envelope lying free 

 in the morbid substance. Some were in the form of the letter S, 

 while others presented a more complex convolution. On scraping 

 a small portion from one of the tumours and mixing it with a 

 little water between two slips of glass, the animals were seen to 

 greater advantage, and their position in the pellucid covering 

 was better defined. On several occasions we saw the animal 

 liberate itself from the membrane in which it was encased ; this 

 was accomplished by the approximation of the head and tail, 

 which were subsequently separated, and driven against the sides 

 of the sac that had previously been elongated, with such force as 

 to rupture it and so set the animal at liberty. In its movements, 

 which were vermicular, the animal showed considerable activity. 

 As it lay extended when quiescent the head appeared of a conical 

 shape, and the tail presented a small, curved, flexible, filiform ap- 

 pendage which was very characteristic (PL V. figs. 1, 2, 3). The 

 integuments being transparent the alimentary canal could be 

 distinctly traced, commencing narrow at the head, enlarging 

 somewhat and terminating near the tail. In some this canal was 

 empty (fig. 2), and the parietes of the tube clearly defined. In 

 others it was occupied with granular matter (fig. 3) having much 

 the appearance of the substance with which they were surrounded; 

 in some instances to such an extent as to fill completely the in- 

 terior of the animal. 



These Entozoa resemble the Trichina spiralis found in mus- 



