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Updated: May 1, 2025
The gizzards of thirty-eight of our common worms were opened, and in twenty-five of them small stones or grains of sand, sometimes together with the hard calcareous concretions formed within the anterior calciferous glands, were found, and in two others concretions alone.
This lower division of the Wealden consists of sand, sandstone, calciferous grit, clay, and shale; the argillaceous strata, notwithstanding the name, predominating somewhat over the arenaceous, as will be seen by reference to the following table, drawn up by Messrs. Tunbridge Wells Sand: Sandstone and loam: 150. Wadhurst Clay: Blue and brown shale and clay, with a little calc-grit: 100.
Calciferous cells adhered to many parts of these mulberry-like masses, and their gradual disappearance could be traced while they still remained attached. It was thus evident that the concretions are formed from the lime contained within the free calciferous cells.
After the formation and expulsion of a large concretion, new lamellae must be developed in some manner. In one section made by my son, the process had apparently commenced, although the gland contained two rather large concretions, for near the walls several cylindrical and oval pipes were intersected, which were lined with cellular matter and were quite filled with free calciferous cells.
These are all branching in form, and many of them are simple calciferous plants, though most of them are true animals, resembling, however, delicate Algae more than any marine animals; but, on examination of the latter, one finds them to be covered with myriads of minute dots, each representing one of the little beings out of which the whole is built.
Nevertheless with several worms collected on such a site, the calciferous glands contained as many free calciferous cells, and fully as many and large concretions, as did the glands of worms which lived where there was little or no lime; and this indicates that the lime is an excretion, and not a secretion poured into the alimentary canal for some special purpose.
The calcareous concretions formed in the calciferous glands, which are often found in their gizzards, intestines, and occasionally in their castings, when of large size, sometimes appeared to have been rounded; but with all calcareous bodies the rounded appearance may be partly or wholly due to their corrosion by carbonic acid and the humus-acids.
From this and other such cases I am led to suspect that the calciferous cells are developed from the larger nucleated ones; but how this was effected was not ascertained. When an anterior gland contains several minute concretions, some of these are generally angular or crystalline in outline, while the greater number are rounded with an irregular mulberry-like surface.
SUBDIVISIONS AND DISTRIBUTION OF STRATA. The Ordovician series, as they have been made out in New York, are given for reference in the following table, with the rocks of which they are chiefly composed: 5 Hudson . . . . . . . . shales 4 Utica . . . . . . . . shales 3 Trenton . . . . . . . limestones 2 Chazy . . . . . . . . limestones 1 Calciferous . . . . . sandy limestones
The sandy limestones of the Calciferous record the transition stage from the Cambrian when some sand was still brought in from shore. The highly fossiliferous limestones of the Trenton tell of clear water and abundant life. We need not regard this epicontinental sea as deep.
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