Page:Popular Science Monthly Volume 2.djvu/102

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THE POPULAR SCIENCE MONTHLY.

If it desires to seize any thing, it protrudes an arm for the purpose; and, when it has in this way got possession of the needed nutriment, becoming all stomachy it wraps itself round its food, and absorbs or digests it.

Dr. Carpenter describes it as "changing itself into a greater variety of forms than the fabled Proteus, laying hold of its food without members, swallowing it without a mouth, digesting it without a stomach, appropriating its nutritious material without absorbent vessels or a circulating system, moving from place to place without muscles, feeling (if it has any power to do so) without nerves, multiplying itself without eggs, and not only this, but, in many instances, forming shelly coverings of a symmetry and complexity not surpassed by those of any testaceous animal."

Fig. 4.
PSM V02 D102 Ciliated infusoria.jpg
Modes of Origin and Development of Ciliated Infusoria. (x600.)

a, Transforming Euglena. with red "eye-speck" still visible; b, A similar body, having many of its chlorophyll corpuscles still green, fringed with almost motionless cilia; c, A completely decolorized sphere derived from a transformed Euglena. provided with a few partly-motionless cilia; d and e, More advanced forms of a similar embryo developing into a Dileptus (?); f, Vorticella. soon after its emergence from a cyst of Euglena origin, which subsequently develops into a striated variety (g); h, A large Chlorococcus-vesicle, whose contents gradually undergo decolorization (j), and at last becomes converted into an annualized mass (k), which gradually shapes itself into the form of an Oxytricha (l). This after a time ruptures its cyst and soon takes on the characteristics shown at m; n, A form of Plœsconia derived from an embryo produced within other, apparently similar, Chlorococcus-vesicles.

The experiments of Dr. Bastian force upon him the conclusion that the several organisms here considered, bacteria, torula, vibriones, fungus-filaments, protomœba, and monads, are products of the direct development of new-born specks of living matter. His experiments seem to have been conducted with extreme precautions. He hermetically closed the narrow necks of his flasks during violent ebullition, thus producing an almost perfect vacuum above the infusion. After