EFFECTS OF GONAD GRAFTS IN CHICKS 27 



Result: Gonads of about the same length on both sides, 4.5 

 mm. Left gonad somewhat broader than the right and unlike 

 a testis as to surface texture. Left miillerian duct of the female 

 type; right duct shortened as in the normal female. 



4. Embryo no. 2-5 (fig. 28). Operated June 21, 1917. Piece 

 of ovary from a young hen grafted on a seven-day-old embryo. 

 Opened, July 2nd. Age of embryo, 18 days; duration of graft, 

 11 days. 



Result: Right gonad, 4.2 mm. long; left gonad, 5.4 mm. 

 Peculiar black pigmentation over most of the surface of the left 

 gonad, thicker over the anterior end. Left miillerian duct 

 present; traces of middle and posterior portions of the right 

 duct. 



5. Embryo no. 17-1 (figs. 29, 30). Operated November 19, 

 1917. Piece of ovary from a month-old chick grafted on a 

 thirteen-day-old embryo. Opened November 26th. Age of 

 embryo, 20 days; duration of graft, 7 days. 



Result: Gonads of the male type, but the right gonad very 

 much smaller than the left one; right gonad, 2.6 mm. long; 

 left gonad, 4.5 mm. long. Left gonad markedly pigmented, 

 except over its posterior end. Wolffian ducts rather of the female 

 type; only posterior portions of the miillerian ducts found. 



6. Embryo no. 17-5 (fig. 31). Conditions of the experiment 

 same as in preceding case. 



Result: Very sunilar to no. 17-1, but size difference between 

 the gonads not so great. Right gonad, 4.2 mm.; left gonad, 

 5.3 mm. Over half of the left gonad pigmented. Wolffian ducts 

 of the male type. Left miillerian duct not well developed; 

 slight trace of the right duct. 



7. Embryo no. 29-7. Operated May 31, 1918. Piece of 

 ovary from a ten-day chick implanted on an embryo of eleven 

 days. Opened June 9th. Age of embryo, 20 days; duration of 

 graft, 9 days. 



Result: Gonads of the male type; right gonad, 4.5 mm. long; 

 left, 5.5 mm. long. The size difference between the two gonads 

 is greater than in the case of normal testes. Wolffian ducts of 

 the male type. Traces of the degenerating miillerian ducts on 

 both sides. 



