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He showed that they were capable not only of surviving the death of the Radiolarian, but even of multipying, and of passing through an encysted and an amoeboid state, and urged their mode of development and the great variability of their numbers within the same species as further evidence of his view.
Again, the cells are modified to form fibers, such as tendon, muscle, and nerve. Even such dense structures as bone, cartilage, and the teeth are formed from cells. Amoeboid Movement of a Human White Blood Corpuscle. In short, cells may be regarded as the histological units of animal structures; by the combination, association, and modification of these the body is built up.
Finally it breaks up into many minute bodies called spores. These bodies break out of the corpuscle and for a time live a free life in the blood. After a time they make their way into other red blood-corpuscles, develop into new malarial amoeboid parasites, and repeat the growth and sporulation. This process can apparently be repeated many times without check.
Rapidly the ends split, one-half being in each fiber set free, and the other remaining fixed, and in 130 seconds each entire flagellum was divided into a perfect pair. Now the amoeboid state is a notable phenomenon throughout the monads as precursive of striking change. It appears to subserve the purpose of the more facile acquisition and digestion of food at a crisis.
The net results of laboratory investigation, according to the French doctors, is that the mycetozoic malarial bacillus, the microbe of paludism, is amoeboid in its movements, acting on the red corpuscles, leaving nothing of them but the dark pigment found in the skin and organs of malarial subjects.
In about forty-eight or seventy-two hours, depending on whether the parasite is vivax or malariæ the wall of the corpuscle bursts and all these spores with the black pigment and the waste products that have been stored away within the cell are liberated into the blood-plasm. These spores are round or somewhat amoeboid and are carried in the blood for a short time.
The first cell-communities to be formed, which laid the early foundation of the higher multicellular body, must have consisted of homogeneous and simple amoeboid cells. The oldest Amoebae lived isolated lives, and even the amoeboid cells that were formed by the segmentation of these unicellular organisms must have continued to live independently for a long time.
Then followed an amoeboid and uncertain form, with an increased intensity of action which lasted a few moments, when lassitude supervened, then perfect stillness of the body, which is now globular in form, while the flagellum feebly lashed, and then fell upon and fused with the substance of the sarcode. And the result is a solid, flattened, homogeneous ball of living jelly.
Fixing on one of these monads then, we followed it doggedly by a never-ceasing movement of a "mechanical stage," never for an instant losing it through all its wanderings and gyrations; We found that in the course of minutes, or of hours, the sharpness of its outline slowly vanish, its vacuoles disappeared, and it lost its sharp caudal extremity, and was sluggishly amoeboid.
When one considers the part which sexual attraction plays in the order of sentient life on the globe, from the almost unconscious attractions which draw amoeboid globule to amoeboid globule, on through the endless progressive forms of life; till in monogamous birds it expresses itself in song and complex courtship and sometimes in the life-long conjugal affection of mates; and which in the human race itself, passing through various forms, from the imperative but almost purely physical attraction of savage male and female for each other, till in the highly developed male and female it assumes its aesthetic and intellectual but not less imperative form, couching itself in the songs of poet, and the sometimes deathless fidelity of richly developed man and woman to each other, we find it not only everywhere, but forming the very groundwork on which is based sentient existence; never eradicable, though infinitely varied in its external forms of expression.
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