George Bidie

“ If we descend the scale of nature, reaching the extreme boundaries, the lowest forms, of the animal and vegetable kingdoms, we find members of these great divisions approximating so closely, that it becomes a matter of difficulty to draw any line of demarcation. The limits here are also hazy, because so far beyond the ken of unaided vision, and although the microscope has unveiled nature's secrets, disclosing a new world grand in the plenitude of its minutiæ, still its scientific eye is finite failing at times to decide which is the animal, and which the plant. ”

“ The heather is a sturdier plant than the rose or the shamrock, and in general hill tribes are endowed with a physical energy superior to that of their Neighbours of the plains. On a poor miserable soil, with scarce vegetation to cover its nakedness, we shall ever find a wretched and thinly scattered population. Looking backwards to the Geological eras of this venerable earth, we also find most wonderful relations, as to rank in their respective kingdoms, existing between the classes of animals and vegetables living at the same time on the stage of the world. ”

“ Thus throughout the two kingdoms we have a contemporaneous progression from the lower to the higher forms, as the earth is changed from an impracticable to the present world with all its beauteous creations, of which man is lord. We find no traces of his footsteps however, in the Palaeozoic or any other formation, until the earth has been made a fit and pleasant habitation for him and his seed for ever. Neither have we a plant of the higher orders, living together with animals or vegetable forms of low caste, during an early fossiliferous era. ”

“ If we now review the function of respiration in the animal and plant, we shall find that although by this process the animal eliminates carbon and consumes oxygen, while the plant fixes the former and gives off the latter, being thus so far opposed in object, they nevertheless agree inasmuch as respiration is carried on in both kingdoms, by means of organs of a cellular structure. ”

“ In plants the root is the great organ of absorption, whether suspended in air, floating in water or buried in the earth. The root consists of a cellular epidermis, and internal structure of vascular bundles and cells. Here then cells are still the great organs of absorption, and if we trace the sap upwards through the alburnum and leaves, and its return through the lactiferous vessels and cells of the bark, we shall find them not less active and essential in the process of assimilation. ”

“ Amongst individuals of humble status, the nutritious matter is at once received through the cell wall by the process of endesmose, to be elaborated and applied in the cavity of the cell to the various wants of the structure. This of all methods is the most simple, and a key to the plans of absorption and assimilation in the higher di- -visions, inasmuch as any apparatus more intricate is merely super- added for the production of a more elaborate nutritious fluid, and its transfer to distant parts of the organism. ”

“ If on the other hand we assume as the characteristic of the animal, its capability of changing its position, we still find similar properties in the plant; for vegetable organisms are in some instances capable of changing their position and performing other movements. ”

“ In whatever direction however the contemplations of the naturalist tend, from race to race or from kingdom to kingdom, he discovers no rude gaps but a beautiful unison, for nihil per saltum is one of the great laws of creation. ”

“ As we compare then these indications of sensibility, and these locomotive powers in the vegetable with the humbler endowments of such an animal as the sponge, which remains through life chained to one little spot of rock, giving out no indications of sensibility, we must at once be struck with the difficulties attending a true distinction, and the intimate relation that exists between the two kingdoms in question. ”

“ In several colonies to which seeds, such as corn and barley, have been sent from Europe, even these sturdy plants suffered from the change of climate, and it was only after the careful culture of a few years that they began to yield an abundant return. On the other hand the agriculturist knows well the advantage of having seed from a limited distance, where there is not any considerable difference in climate involved in the change. ”

“ True we find numerous examples of ceils that do not exhibit even the trace of a nucleus, but from these it may either have been removed by absorption, or it may be destin- ed to appear at some future era of their existence. The modes of Cylogenesis are various, but nearly all agree in being common to the animal and vegetable. To the older Physiologists the subject of reproduction was fertile in speculation and romance, and it was only wh^n the theory of cells and their development became known, that we were able to read its history in the earlier and more myste- rious stages. ”

“ Thus plants in some instances seem capable of distinguishing between light and darkness, for many only open their leaves or flowers to the sunshine, while others the plantæ tristes, the watchmen of the flower garden, only spread abroad their beauties to the night. ”

“ Those at all conversant with a pastoral life also know the change in height and appearance that takes place in the Shetland breed of ponies, when transported young from their native shores to the south of Scotland or to England. ”

“ Other plants exhibit a certain amount of irritability, or sensitive qualities, under mechanical or chemical stimuli. The Drosera and Dionæa woo the unwary fly to its destruction shutting it up in deadly folds, while the Mimosa sensitiva and a few others will shriek from the most delicate touch, and may be laid asleep, during any severe operation of the gardener, under the influence of opium or Chloroform. ”

“ The individual cells concerned in the manufacture of the various secretions, as they disclose no appreciable disparity in structure to account for the dissimilarity of their products, must therefore possess some special endowment or quality, whereby they are enabled to make a selection of material. ”

“ In each and all of these periods of Geological history, we find certain classes of animals co-existing with consonant grades of vegetable productions. We find not a single departure from this rule, for throughout all the works of the great Creator there is a constant harmony. ”

“ In the higher animals and plants, the process is com- plicated in accordance with the general plan of organization, but as we approach the simple infusorial animal or cryptogamic plant, w^e can with facility explore the plan of nature's grand secret. Here new generations originate in accordance with the laws of Cytoge- nesis, the nucleus of the parent preparing a future race, or some of the other systems obtaining by which the old cell begets the new. ”

“ We now come to consider some ©f the functions of organic life, premising that in all organs where these vital operations are car- ried on, we find a true cellular structure retained. Beginning with absorption and assimilation, we fiad these processes varying, ac- cording to the rank of the animal or plant, in the respective kingdoms, but still agreeing in the constant cellular agency. ”

“ Tl^e smallest of the Infusoria, the most minute Cryp- togam are but simple cells living an independent isolated life, and every living structure however complex, however strange, has had a cellular origin, and is indebted for its growth and maintenance to the modification and development of cells. [2] The cell consists of an enveloping membrane or cell wall, that encloses a peculiar fluid and nucleus or cell-germ. ”