Explanation of Plate.

A FIG. 1. Œsophagostoma columbianum, Curtice.

                    Head x 280 diameters. The two padilke which serve as openings of
the lateral canals are seen on either side. Of the other four tubercles,
only one is shown, to avoid confusing the outlines of the armature.

    "      2. Split preparation of the head of the same x 280 diameters showing, first, a
ring of plates with semilunar ends, next the circlet of fimbriæ, and
lastly, the circlet of bidentate teeth, below which is the wide œsophagus.

    "      3. Bursa of male Œsophagostoma partially spread x 70 diameters.

    "      4. Ovum of Œsophagostoma x 440 diameters taken from the clot adhering
to the vulva.

    "      5. Trichonema stage of Œsophagostoma from tumour of intestine of sheep.

    "      6. A portion of the large intestine of a sheep affected with nodular disease
of the intestine. Natural size.

B. Trichosomum verrucosum, sp. n.

    "      7. Trichosomum verrucosum, ♀, natural size.

    "      8. Head of the same x 28 diameters.

    "      9. Caudal extremity of the same x 28 diameters—

                                       a —anus.

                                       v —vulva.

                                       u —uterus.

                                       i —intestine.

   "      10. Ovum of above, from uterus x 440 diameters.