The observation of serial sections of art embryo related with the pig and chick embryos.

ABSTRACT

Serial sections of 4 mm. and 6 mm. of the rat embryos were carefully studied in relation to the serial sections of 36 somites chick embryo and 10 mm. pig embryo under low power microscope to compare their organogenesis. Most of the organs developed in the same manner except for the smaller mesonephros in the rat embryo which appeared to be smaller than in the pig embryo. Neither subcardinal vein nor subcardinal anastomosis coved be observed in these two stages of the rat embryos.