Extravital

The biochemist hopes to make protoplasm in a beaker, but in transforming his homogeneous jelly into a ‘sprig of moss’ he will need to utilize agencies not only unexplained, but not even analogous to the postulates or properties now ascribed to unorganized matter. These agencies or properties of life are doubtless as ‘natural’ as those treated in physics and chemistry, but they are different. To call them ‘creative’ or ‘directive’ is, perhaps, open to objection, but they are certainly conservative, coordinative and constructive in a manner and degree for which we have no extravital analogy. The directive idea, however, is by no means extinct among biologists.

The sole limitation appears to be the restriction of the chromatic granules ordinarily to the nucleus, while, on the other hand, the linin network of the nucleus appears to have the same granular structure as the cytoplasmic reticulum, and the nuclear membrane appears to originate in a condensation or felting of the same substance. Can we then associate these granules with the ultimate units of life? Yes and No. Yes, in the sense that such a chromatin granule associated with short filaments radiating from its core, supported and extended by a unit mass of nucleoplasm,! affords us a theoretic unit capable of growth and division in its particular environment—incapable, however, of an extravital existence. No, in the double sense that on the one hand we can hardly suppose that the ultimate units of living matter happen to coincide with the revelations of the most powerful microscope of the twentieth century; and that on the other hand if we insist on independent existence in a purely physical environment such a suggested unit fails to respond to the criterion.

The peculiar substance resembling fibrin which we have described in the glomerular spaces of animals poisoned during life was also found in the extravital experiments.

The extravital existence of the bacilli in the excavated lung of the patient appears to parallel similar laboratory cultivation in that some artificially cultivated bacilli tend to become less virulent, or in special cases become avirulent. This patient, however, became acutely ill with the infection caused by the avirulent tubercle bacilli and died apparently not from tuberculosis but from tuberculous allergic bacillary intoxication caused by the large amounts of avirulent tubercle bacilli harbored in the lungs.