SMOLTS 21 
and growing in the estuary, as sea trout appear to 
do, and that in making their descent they forsake 
the shallows for the main current. In rivers which 
flow directly into the sea with little or no natural 
estuary, such as the Spey, Dee, or Helmsdale, the 
transference of the smolts must be comparatively 
rapid, but in such localities a considerable body of 
fresh water no doubt spreads itself out delta-wise 
over the denser sea water in such a manner that the 
necessary conditions are supplied to the smolts. It 
seems certain that just off or at the mouths of such 
rivers the smolts are in great numbers in May and 
June, and at times fall an easy prey to coal-fish and 
other members of the cod family. The mouth of the 
Spey has been occasionally netted when smolts were 
seen to be descending, and great quantities of coal- 
fish captured and destroyed or given away. The 
stomachs of those fish were found to be full of 
freshly swallowed smolts. It appears, however, that 
the coal-fish do not always time their visit correctly, 
since on more than one season of smolt descent a 
very large draft net failed to capture any of them. 
It has been said that in netting the upper tidal 
waters of the Tay at Kinfauns parr of very varying 
sizes are found. Some of those little fish are not 
more than an inch and a half to two inches in length. 
Without doubt many gravid adult fish entering the 
river during the actual spawning season—and it may 
be stated here that ripe male fish come in from the 
sea in full red spawning livery, as netting in close 
time for experimental purposes fully shows—that 
these gravid fish make their redds and spawn almost 
