Fig. 3. The pentastoma. Hitherto supposed to exist only in the dog and wolf, but discovered recently in the frontal sinus of the sheep by my friend Mr Rhind of Edinburgh, by whom the drawing for this figure was kindly furnished.
Fig. 1. Hydatid in the brain of a sheep (from a drawing by my friend Dr Kirk of Deal); a. the right lobe of the cerebellum or lesser brain distended with fluid, inclosed in a membraneous bag, as shown at b., where an incision has been made to expose it; and at c. where it is shining through the pia mater, one of the coverings of the brain.
Fig. 2. Showing the extent to which hydatids sometimes distend the ventricles of the brain; a. the dilated ventricle of the left side; b. b. convolutions passing from back to front; c. d. depth of the furrows.
THE SHEEP.
CHAPTER I.
HISTORY OF THE SHEEP.
(1.) Origin of the Sheep.—As the origin of our domesticated animals has afforded scope for much curious speculation, so none have attracted a greater degree of attention in this respect than the sheep. Into these arguments, however, it would be absurd to enter; I shall therefore content myself with such opinions as are deemed the best.