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 To mount the specimens for the microscope all that remains to be done is to take as many as will lie on the point of a knife and boil them for a short time in a test tube containing a little turpentine. This is done to expel the air from the shells. Transfer a few of the specimens to the centre of a glass slip. add a spot of Canada balsam, and immediately place a thin cover glass on, and when dry finish off according to taste. The slides thus inexpensively provided will then be ready to answer the enquiry "What does the chalk contain?"



The few nematoid parasites that remain to be considered comprise several rare end interesting species, and likewise two of the commonest intestinal worms. What I have incidentally advanced respecting the strange way in which the old writers confounded Guinea-worms with the serpents, finds noteworthy confirmation in the circumstance that the great strongyloid kidney-worm has also been looked upon as a species of venomous ophidian reptile, acta of this order, if duly weighed, inevitably cause us to modify our interpretation of the statements made in ancient records. Thus, to return to the Guinea-worm. Whatever good the theosophical remedies recommended and enforced by Moses may have accomplished for the human victims suffering from the attacks of "fiery serpents," or Dracunculi, it is to be feared that no similar remedial measures of the mystified kind could be rendered available in the case of animals bitten by parasites that have been regarded as renal serpents. It is fortunate, indeed, for man that the great kidney-worm (Eustrongylus gigas) has only once been detected in the human body. If this formidable entozoan, capable of attaining length of three feet, were as common in man as it is in certain animals, no doubt the superstitions people of southern climes would readily invoke clerical aid in view of obtaining miraculous cures. Possibly a mitigation of their sufferings might follow such exhibitions of human sympathy and trust. The case of animals, however, is very different. The unfortunate wolves of the Pyrenees cannot, of course, he expected to secure any very large amount of sympathy; nevertheless, it is the business and duty of the helminthologist to point to the causes of the sufferings of all kinds of animals, whether wild or domesticated, and so far as lies in his power to suggest the means whereby their sufferings may be mitigated. Not only do solitary and large nematoid parasites take up their abode in essentially vital organs of the body, and thus secure the slow destruction of the host, but the minutest forms of the same group