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. [Footnote:
_Trans. Pathol. Soc._ (London), vol. 57, Part i., 1906.] 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 consisting entirely of tubuli lined by an epithelium consisting 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. The
left and larger gonad had a quite similar structure, but at its lower end
were found two ova enclosed within a follicular epithelium.

With regard to the last case it is to be remarked that though the gonad on
the right side was entirely male, there was no unilateral development of
male characters. With regard to the other two cases it must be pointed out
(1) that the difference between the two somatic sex-characters on the two
sides is chiefly a difference of colour, except the difference in the
spurs in Bond's pheasant; (2) that the evidence already cited shows that