ROBERT DABORNE’S PLAYS. II. The Poor-Mans Comfort.

The origin of erythrocytes in herring ( Clupea harengus )

“…It has been shown th a t the chief place of erythroblast-formation is the intermediate cells mass which extends from the level of the anterior portion of the kidney into the tail of the embryo and the yolk-sac blood islands, which are formed by the migration of wandering cells at a very early period. The chief source of the origin of erythroblast is therefore seen to be the inter mediate cell mass which was previously described by Swaen and Brachet (1901) and Felix (1897), but contrary to their conclusion it has been shown th at the mesoblast cells of the intermediate cell mass, instead of being indifferent stem mother cells which gave rise to both ervthroblasts and leucocytes, definitely form only the erythroblasts.…”

“…For a precise com prehension of the development of the blood and vascular system it is only necessary to consider the opinions of some of the recent workers on the subject. According to Swaen and Brachet (1901) the mesoblast in the posterior half of the embryo consists of an inner primary somite portion and an outer primary lateral plate part. In the mid-body region a portion of the primary lateral plate part adjacent to the somites divides off and forms a mass of intermediate cells.…”