ANKERITE VEINS OF LONDONDERRY—LOUIS. 47 
We find also, principally from the Fishery Reports, the follow- 
ing facts :-—That Salmon are more vigorous, and their ova equally 
fertile, that have never been in fresh water, but have been kept 
in tide-way reserve ponds. (Reports of Tadousac Breeding Es- 
tablishment). That the Ontario Salmon on the contrary never 
go to salt water, but are equally vigorous, (see Mr. R. Wilmot’s 
' reports,) and that a few in Nova Seotia resist the fresh water 
changes. These facts are all comparatively new, and bearing as 
they do, so strongly upon the question of what are called land- 
locked Salmon, by many scientific men, still in the United States 
Fishery Commission, they are well worthy of a most minute, 
exact and scientific series of new observations, which might be 
made with little expense, if connected with the various fish 
breeding establishments of the Dominion. The growth of scale, 
the discolouration of flesh and of body, the changes of teeth and 
jaws in the male, and the peculiar changes in the pyloric cceca 
in fresh water and ocean fish (lately pointed out by R. Morrow, 
a member of our Institute) as taking place in the three forms of 
all fresh water, all salt water, and partly fresh and salt water, 
with exact dates and minute comparisons, would well reward 
the attempt, and be a small boon from the Government to her 
men of science. 
Art, VIII.—On THE ANKERITE VEINS OF LONDONDERRY, NOVA 
Scotia.—By Henry Louis, Assoc. R. Society, Mines, 
London. ; 
(Read March 10th, 1879.) 
EXTENDING along the base of the southern slope of the Cobe- 
quid mountains, and parallel, roughly speaking, to the mountain 
axis, is a remarkable series of fissure veins, filled with a number 
of interesting minerals, of which, as at present known, the most 
plentiful and the most characteristic is the Ankerite. These 
veins, which I shall in this paper designate the Ankerite veins, 
although Ankerite is not by any means their sole constituent, 
occur in a band of slate and shale, varying in colour from a dark 
blue to a pale olive green, and forming apparently the topmost 
