Synoptic table of the Carnegie stages 20 - 23 Stage 20 Approx. 49th day 18 - 22 mm Fig. synopimg20 - Embryo stage 20, ca. 49 days Liver prominence Primordium of the eyelid Eye Auditory canal Elbow Fingers Toes being formed Straightening of the trunk Subcutaneous vessel network of the head Cervical flexure Legend Fig. synopimg20 Characteristic signs Arms in pronation. Separated fingers. Gonadal gender determinable in female embryos. © Professor Kohei Shiota, Kyoto University Stage 21 Approx. 51rst day 22 - 24 mm Fig. synopimg21 - Embryo stage 21, ca. 51 days Umbilical cord with physiologic hernia Nose Subcutaneous vessel network of the head Ear Elbow Pronation of the hands (pink arrow) Knee Supination of the feet (blue arrow) Toes Legend Fig. synopimg21 Characteristic signs Subcutaneous vessel network of the head spreads out. Hands and feet come closer and touch each other. © Professor Kohei Shiota, Kyoto University Stage 22 Approx. 53rd day 23 - 28 mm Fig. synopimg22 - Embryo stage 22, ca. 53 days Umbilical cord with physiologic hernia Nose Subcutaneous vessel network of the head Ear Elbow Pronation of the hands Knee Supination of the feet Well-developed toes Remainder of the embryonic tail Legend Fig. synopimg22 Characteristic signs Development of the eyelids and the external ear canal. Tragus and antitragus. Nasal septum. Secondary palate. © Professor Kohei Shiota, Kyoto University Stage 23 Approx. 56th day 27 - 31 mm Fig. synopimg23 - Embryo stage 23, ca. 56 days Umbilcal cord with hernia Nose Eye Eyelid Ear (a: tragus, b: antitragus ) Mouth Elbow Finger Toes Atrophied embryonic tail bud Telencephalon Diencephalon Mesencephalon Metencephalon Myelencephalon Spinal cord Legend Fig. synopimg23 Characteristic signs Angle between the head and trunk amounts to 30°. The head makes 50% of the embryo's size. The head is rounded, the extremities lengthened and stand out from the body. Chin. Nasal pit. Development of the external genital primordium. © Professor Kohei Shiota, Kyoto University