On the Else of the Shores of the Firth of Forth. 297 
a dead shell in it one foot above the present limit of Pholas 
life. But perhaps they may urge that the Lithodomi were 
introduced by the Komans. Until this proof is produced all 
their other arguments are futile. 
Another argument against this theory, and I have done. 
The Kev. William Nimmo, minister of Bothkennar, in his 
" General History of Stirlingshire/' published in 1787, thus 
describes the Roman road near Stirling : — 
" The peculiar form and regular dimensions, together with 
the straight course, easily distinguish it from other cause- 
ways. Nearer to the Drip, too, its foundations have been 
lately digged up. The ford hath a firm and solid bottom, 
and during the summer season little above two feet of water. 
There was no occasion for a bridge to transport the hardy 
sons of Eome, whom much more stately rivers did not 
intimidate from their darling project of subduing and 
plundering the world." 
If, then, tliis ford, as described by Nimmo, was only two 
feet under water in 1787, and the land had risen 25 feet, 
surely the legs of the horses used by the Romans must have 
been unusually long. This ford is still in use, and I hope 
will be a lasting testimony of the folly of believing that any 
rise has taken place on the shores of the Forth within the 
human period. 
II. Remarks on the assmnption of Male Plumage hy the Hen of the 
Domestic Fowl. Bj William Tukner, M.B., F.R.S.E. 
The specimen shown by the author to the Society fur- 
nished an excellent illustration of the change in external 
characters which female birds of the gallinaceous order 
sometimes exhibit. It was a bantam hen, and was sent to 
the author by Dr Alexander Dickson of Hartree, and will 
be deposited in the Anatomical Museum of the University. 
The bird was thirteen years old at the time of death, four or 
five years before which it had ceased to lay eggs. About a 
year before death the bird began to assume the external 
characters of the male, which were best marked in the 
plumage, more especially in the form of the tail-feathers. 
