156 EVIDENCE OPPOSED TO 



Another case in birds was described by Poll 1 and 

 is mentioned by Doncaster. 2 It is that of a Bullfinch 

 which had the male and female plumage sharply 

 separated on the two sides of the body. The right 

 side of the ventral surface was red like a normal 

 male, the left side grey like a normal female. In this 

 case there was a testis on the right side, on the left 

 an ovary as in normal females. 



A third case in birds, somewhat different from 

 the two first mentioned, is that of a domestic fowl 

 described by Shattock and Seligmann. 3 It was a 

 bird of the Leghorn breed, two years old, and had 

 the fully developed comb and wattles of the cock. 

 Each leg bore a thick blunt spur, nearly an inch in 

 length, but in the Leghorn breed spurs are by no 

 means uncommon in hens of mature age, before they 

 have ceased to lay eggs. In plumage the characters 

 were mainly female. The colour being white could 

 not show sexual differences, the neck hackles were 

 but moderately developed, saddle hackles practically 

 absent, the tail resembled that of the hen. There 

 was a fully developed oviduct on the left side, on the 

 right another less than half the full length. There 

 was also a vas deferens on each side. There was a 

 gonad on each side, that of the right about one 

 fourth the size of that on the left. In microscopic 

 structure the right gonad resembled a testis con- 

 sisting entirely of tubuli lined by an epithelium con- 

 sisting of a single layer of cells. In one part of this 

 organ the tubules were larger than elsewhere, and 

 one of them exhibited spermatogenesis in progress. 



1 S.B. Qes. Naturf. Freunde, Berlin, 1909. 



2 Determination of Sex, Cambridge, 1914. 



8 Trans. Pathol Soc. (London), vol. 57, Part i., 1906. 



