배아(Streeter연령균 XXII)의 1예

Abstract

A human embryo was obtained from a hysterectomy specimen from a 41 years old woman who was operated for the termination of pregnancy. The embryo was 23.6mm, in length, and it was serially sectioned in 4,um thickness and reconstructed with 701 section slides. This embryo was cbaracterized by the thick cornea forming the mesothelial layer, the optic nerve beginning to form the sheath layer, turning down and transitional stage of cochlear tip, remnant of incomplete stalk of the hypophysis, reduced oral opening of the vomeronasal organ, the submandibular gland with the definite lumen in the oral part of the duct and much branched long duct, few large spoon-shaped capsule of the kidney with short secretory tubules and early shaft shell in the cartilage and bone. From above findings, we concluded that this em bryo belonged to the age group XXII of Streeter's developmental horizon.