THE ETIOLOGY OF BURSATI                                    235

Smith, F. (1884). Vet. J. 19,16.
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Smith, Theobald. (1893-94). 10th and 11th Ann. Rep. Bur. Ani. Indust.
Spitz, G. (1920). Trap. Vet. Bull. 8, 202.
Spooner, Hart. (1873). Veterinarian, 46, 386.
Steel, J. (1881). Vet. J. 13, 237.
— (1884). Vet. J. 18,132.
Ubique, (1877). Vet. J. 5, 25.
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                             DESCRIPTION OF MICROPHOTOGRAPHS.

Plate XIV, fig. 1.—Low power photograph of a section of bursati growth, removed from the
              angle of the mouth, showing a typical habronemic abscess in the early lymphocytic
              stage. In the central degenerated area, both longitudinal and cross-sections of the larvao
              can be seen. The histological picture resembles very closely that of early gastric
              abscesses, due to H. megastoma.
Fig, 2.—Low power photograph illustrating the essential lesion of Bursati, characterised by a
              cross-section of the parasite, enclosed in a blood vessel, around which a lymphocytic
              infiltration can be seen arranged in the form of a nodule. This is the earliest stage in
              the formation of the kunkur.
Plate XV, fig. 1.—Section of a bursati growth, removed from the limb, showing a coiled larva
              in a dilated vessel. Note the sharp outline of the lumen and that the concentration
              of the toxic effect on the vessel wall diminishes from the centre outwards.
Fig. 2.—Same as PI. XIV, fig. 2 but under a higher magnification. The worm larva is seen
              here at its primary seat of operation, the lumen of a capillary vessel.
Plate XVI, fig. 1.—Low power photograph of an exceptional section of a growth. Superficial
              cutis shows degenerative changes, with a slight involvement of two epithelial papillae in
              the centre of the field. Sub-epithelial layer is practically unaffected, excepting for slight
              eosinophile infiltration.
Fig. 2.—Low power photograph of a bursati section. An elongated kunkur, which is more
              extensive in the depth of the growth than towards the surface, is seen here, having been
              formed along the course of one of the dilated perpendicular vessels. Note the partial
              loss of staining affinities of the major portion of the field, compared to the darker and
              healthier portion on the left.
Plate XVII, fig. 1.—Low power photograph. On the left, four kunkurs are to be seen. In
              the case of the lowest kunkur, the centrally situated blood vessel can be seen, as also the
              diffusion of the toxin for the same distance in all directions, giving a more or less
              rounded appearance to the kunkur.
Fig 2.—Low power photograph, showing two kunkurs in a bursati section. The left one is
              practically free to be evacuated from the fistula in the mother tissue. The right one
              has been formed in a hair follicle, the hair root having already been destroyed.

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