Angioblast
From Infogalactic: the planetary knowledge core
Blood vessels first make their appearance in several scattered vascular areas that are developed simultaneously between the endoderm and the mesoderm of the yolk-sac, i. e., outside the body of the embryo. Here a new type of cell, the angioblast or vasoformative cell, is differentiated from the mesoderm.
These cells as they divide form small, dense syncytial masses, which soon join with similar masses by means of fine processes to form plexuses.
Angioblasts are one of the two products formed from hemangioblasts (the other being multipotential hemopoietic stem cells).
References
This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)
