Fluke In Sheep. TO THE EDITOR.

Otago Witness, Issue 2179, 28 November 1895, Page 7

Fluke In Sheep. TO THE EDITOR.

Sir,— Mr M'Gregor's account of the cau3e of fluke in sheep is widely at variance with that of the New South Wales expert, and all other investigators so far as I know. The fluke is a perfect parasitic worm, not in any way related to any " fly " of any sort. Reference to text-books, where available, will confirm this statement, and any encyclopedia published within the last 20 or 30 years will. I think, do the same. If Mr

M'Gregor can quote any authority for his cu'ious account of this parasite I will be most interested to look up same. In tho meantime I quote from a recent most excellent work * a concise epitome of the liver-fluke's life history. Of such organisms its author says : — "Those which are internal boarders have an intricate fife-cycle, requiring to pass from one host to another of a different kind if their development is to be fulfilled. Thus the liverfluke (Distumum hepatscum), which causes the disease of liver-rot in sheep, and sometimes destroys a million in one year in Britain alone, has an eventful history. From.the bile-ducts of the sheep the embryos pass by the food caual to the exterior. If they reach a pool of water they develop, quit their egg-hells, and become for a few hours frce-bwimming. Th<-y kuock against many things, but wben they come in contact with a small water-snail mucous truncatulus) they fasten to ifc, bore their way in, and, losing their locomotor cilia, encyst themselves. They grow and multiply in a somewhat asexual way. Cells within the body of the encysted embrjo giva rine to a second generation quite different iv form. The second generation similarly produces a third, and so on. Finally, a generation of little tailed flukes arises ; these leave the water-smtil, leave the water too, settle on blades of grass, and lose their tails. If they be eaten by a fheap they develop into adult sexual flakes. Others have nob less eventful life-cycles, bnt that of the liver-fluke is most thoroughly known." The italics aro mine. — I am, &c, Dinornis.