CHROMATIN BRIDGES AND IRREGULARITY OF MITOTIC COÖRDINATION IN THE PENTATOMID PEROMATUS NOTATUS AM. AND SERV

¹ From the Department of Zoölogy, Columbia University, New York City

1. The abnormal course of meiosis in a specimen of Peromatus notatus is characterized by a series of well-defined irregularities.

2. The spindle of the first division shows both centers to one side of the geometrical axis and the metaphase plate displaced to the opposite side.

3. Before the chromosomes of the first division have reached the poles, they are subjected to the forces involved in the second division.

4. The effect on the chromosomes is to attenuate them without bringing about a normal division. The resulting configurations simulate inversion bridges, though that is quite clearly not their nature.

5. The spermatids receive varying amounts of chromosome material and are multinucleate.

6. It is suggested that this abnormal meiosis is due to an irregularity in the timing of one of the mitotic processes. The indications are that this process involves the movement of the centers.