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Show 8 HABITS OF WORMS, CHAP. I. CHAPTER I. HABITS OF WORMS. Nature of the sites inhabited-Can live long under waterNocturnal- Wander about at night-Often lie close to the mouths of their burrows, and are ' thus destroyed in lar!!C numbers by birds-Structure-Do not possess eyes, but can distinguish between light and darkness-Retreat rapidly wh n brightly illuminated, not by a reflex action-Power of attention -Sensitive to heat and cold-Completely deaf- ensitive to vibrations and to touch-Feeble power of smell-Tast - Mental qualities-Nature of food-Omnivorons-DigestionLeaves before being swallowed, moistened with a flnid of the nature of the pancreatic secretion-Extra-stomachal digestion -Calciferous glands, structure of-Calcareous concretions formed in the anterior pair of glands-The calcareous matter primarily an excretion, but secondarily serves to neutraliHe the acids generated during tho digestive process. EARTIT-WORMS are distributed throughout the world under the form of a few genera, which externally are closely similar to one another. The British species of Lumbricus have never been carefully monographed; but we may judge of their probable number from tho::se inhabiting neighbouring countries. In Scanrlinavia there are eight species, according to CJIAP. I. SITES INIIABITED. 9 Eisen ; * but two of these rarely burrow in the ground, and one inhabits very wet places or even lives un ler tho water. We are here concerned only with the kinds which bring up earth to the surface in the form of castings. Hoffmeister says that the species in Germany are not well known, but gives tho same number as Eisen, together with some strongly marked varieties.t Earth-worms abound in England In many different stations. Their castings may be seen in extraordinary numbers on commons and chalk-downs, so as almost to cover the whole surface, where the soil is poor and the grass short and thin. But they are almost or quite as numc·rous in some of the London parks, where the grass grows well and tl1e soil appears rich. Even on the same field worms are much more frequent in some places than in others, without any visible difference in the nature of the soil. They aLound in paved court-yards c]ose to houses; and an instance will be given in which they had * 'Bitlrag Lill Skandin:wiens 01igochrotfauna,' 1871. t 'Die b1:; jetzt bekannten Arten aus der Familio uer Regen· wUrmer,' 18 15. , |