. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 518 stage a number of long chromatin bodies, each of which is split longi- tudinally (Fig. 11). At the middle point of these segments the split is wider than elsewhere, and this marks the region of an ensuing transverse division which corresponds to the separation of the ends of the Vs in Anasa. The segments are never bent sharply at this point at they are in Anasa, though, as will be described later, they may be greatly curved. These segments now condense, and all traces of the longitudinal split are either entirely lost or
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 518 stage a number of long chromatin bodies, each of which is split longi- tudinally (Fig. 11). At the middle point of these segments the split is wider than elsewhere, and this marks the region of an ensuing transverse division which corresponds to the separation of the ends of the Vs in Anasa. The segments are never bent sharply at this point at they are in Anasa, though, as will be described later, they may be greatly curved. These segments now condense, and all traces of the longitudinal split are either entirely lost or are only recognizable as faint constrictions at the ends (Fig. 12). The transverse con- striction is much more prominent, and the chromosomes resemble those shown in Montgomery's Figs. 4 and 5. Before going into the division of these tetrads we must describe the rings which are frequently found in these forms and which are of considerable interest and importance as they are unlike any pre- viously described. These rings are formed in the following manner; a long longitudinally split segment such as Fig. 11 becomes curved so that its opposite ends approach each other (Fig. 13), and finally fuse to form a ring-like body (Fig. 14). As the segment from which this body was formed was split longitudinally and consisted of two halves parallel to each other, this body really consists of two rings, parallel to each other. The body now has somewhat the appearance of a finger ring from which the stone has been removed; the wider portion, which is opposite the point of fusion of the ends of the segment, represents the wider middle region of the long segment (Fig. 11), and thus corresponds to a transverse division. The chro- matin contracts, the rings becoming smaller (Fig. 15), and finally the parallel rings fuse together to form a single one, which shows its double origin only by a faint constriction. Then the rings break across again at the point of fusion (Figs. 16 and 17), and this Fig
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