Specific Form. Living Bodies and Crystals.
§ 1. Specific form and chemical constitution—The wide distribution
of crystalline forms—Organization of crystals—Law
of relation between specific form and chemical
constitution—Value of form as a characteristic of brute
and living beings—Parentage, living beings and mineral
parentage—Iso-morphism and the faculty of cross-breeding—Other
analogies. § 2. Acquisition and re-establishment
of the specific form—Mutilation and regeneration of crystals—Mechanism
of reparation.
§ 1. Specific Form and Chemical Constitution.—In
the enumeration which we have made of the essential
features of vitality there are three that are, so to
speak, of the highest value. They are, in the order of
their importance:—The possession of a specific form;
the faculty of growth or nutrition; and finally, the
faculty of reproduction by generation. By restricting
our comparison between brute bodies and living
bodies to these truly fundamental characters we
sensibly restrict the field, but we shall see that it
does not disappear.
Wide Distribution of Crystalline Forms.—The consideration of specific forms shows us that in the mineral world we need only consider crystallized bodies, as they are almost the only ones that possess definite form. In restricting ourselves to this category we do not limit our field as much as might be sup-
