The development of kidney and gonadof 3-6th-week human embryos were studied.Their positions at different developing stageswere measured in terms of the sequence ofneural ganglion according to Felix's method.The 9.5 mm embryo: Pronephrons are seenas 2 epithelial blind tubules on the rightside and 1 on the left at the 6th cervicalganglion level. The lateral tubule on theright side and the left one are pronephricducts, whereas the medial one on the rightside is the pro n ephric tubule. The cranialends of meson...