The Scottish Naturalist. 
in changing Loch Lomond from a salt to a fresh water loch, there 
must have been a very great lapse of time before the physical 
features of the loch itself and the surrounding country assumed 
their present form, and that during this period a condition of things 
existed favourable to the presence and propagation of the many 
groups of coarse fishes which flourish in swampy, marshy sur- 
roundings. 
It is the presence of a considerable assemblage of such fishes 
which constitutes the chief distinctive feature of the Loch Lomond 
fish-fauna ; and I believe we may search Scotland in vain for a 
similar concourse of species ; for, as will be seen by the following 
catalogue, we here find, besides almost all the accepted species of 
true Salmonidae known in Britain, and the Coregonus, an aberrant 
member of that group, no less than 14 species of coarse fish which 
may be considered indigenous, and many of which are rarely met 
with in the company of the nobler sporting fishes of the salmon 
tribe. 
The most notable absentee is the char, a fish inhabiting many 
of our Scottish lakes, principally those of an alpine character, and 
which one would expect to find amongst the inhabitants of a 
deep, cold, clear loch such as that under consideration. It is 
probable that the comparatively recent marine condition of Loch 
Lomond, and its palustrine rather than alpine connection, is a 
sufficient reason for the absence of this fish. 
The tributary streams are numerous, and drain an immense 
tract of country. Beginning at the head of the loch we have the 
Falloch, a stream much frequented by sea trout, but whose upper 
waters are cut off by a precipitous fall, quite impassible to fish. 
Passing down the Dumbartonshire side we come to the Garabal, 
a small stream issuing from a loch of the same name high up 
among the hills, which holds brown trout of very excellent quality. 
Next is the Sloy water, issuing from Loch Sloy, a lake about a 
mile long, lying 4 or 5 miles inland, swarming with brown trout 
of small size ; farther down, between Tarbet and Luss, is the 
Douglas, a- stream of some size, but, like the Falloch, cut off as a 
spawning ground for sea trout by a steep broken fall a short dis- 
tance from the mouth. Lower down are the Luss and Fruin, 
which rise in the glens of the same names and afford, during 
their entire course of six miles and eight miles respectively, ex- 
cellent spawning ground for brown trout, salmon, and sea trout. 
