Gen. r. 



THE DEVELOPMENT OF THE UROGENITAL SYSTEM. 425 



Umb. c. 



":< ..^ 



^ 



-*.'. Umb. c. 



Gen. tub. 



do. and 

 gen. f. 



GI. p. 



FIG. 385. FIG. 386. 



FIGS. 381-386. Stages in the development of the external genital organs. Kollmann's Atlas. 

 FIG. 381, " indifferent " stage embryo of 17 mm.; Fig. 382, " indifferent " stage embryo of 23 mm-; 



Fig. 383, " indifferent " stage embryo of 29 mm. (beginning of 3d month); Fig. 384, female 



embryo of 70 mm. (n weeks); Fig. 385, female embryo of 150 mm. (16 weeks); Fig. 386, 



male embryo of 145 mm. (16 weeks). 

 An.y Anus; Cl., clitoris; Clo.and gen. /., cloaca and genital folds; CL m., cloacal membrane; Ext., 



lower extremity; Gen. /., genital folds; Gen. r., genital ridge; Gen. yw., genital swelling; 



Gen. tub., genital tubercle; Gl. p., glans penis; Lab. ma., labium majus; Lab. mi., labiura 



minus; Ra., raphe of scrotum; Scr., scrotum; Ta., tail; Ug. s., urogenital sinus; Umb. c^ 



umbilical cord. 



