Note 24 — LECTURE XIX

Boveri has recently made an observation upon the thread-worm of the horse, which points to the correctness of the conception of the germ-plasm. The two first segmentation-cells both receive the four chromosomes of the species, but, in one of the two, a portion of the chromatin breaks off and degenerates, or dissolves, at least as far as can be seen. The other cell retains the whole mass of chromatin, and from this there arise later the primitive genital-cells. In the germ-track, therefore—so we must interpret it—the whole of the germ-plasm is retained, while a part of it is withdrawn from the soma. I have only partly described the process, and I do not wish to enter in detail on an interpretation of it, since it seems to me obscure and to require further observations before an interpretation can be attempted with any confidence.