The Scottish Naturalist. 
117 
The following is the Catalogue of these fishes so far as observed 
by me : — 
Petromyzon fluviatilis, Linni\ the River Lamprey. 
Stone Eel. Nine eyes. 
Very common in the loch, remaining tliere all the year round, 
and ascending the streams in the month of April to deposit their 
spawn. When engaged in this operation they assemble in groups 
of 20 or 30 individuals of both sexes on the shallow fords, 
where they scoop out a redd, or trench, in the gravel, in v/hich 
they deposit their spawn promiscuously. The redd is then again 
covered up with gravel, and the eggs left to hatch out. This 
small species, which seldom exceeds 12 inches in length, or 
weighs more than an ounce, attacks and destroys all sorts of fish, 
but more especially brown trout and powans, the latter falling 
easy victims to its voracity, and they m^ay frequently be seen floating 
on the surface of the water with the lamprey attached, its jaws 
and head buried in the flesh of its victim. 
In England this fish is sought after as. bait and, occasionally, for 
the table ; but it is not reckoned of any value with us. 
Petromyzon marinus, Limit, the Sea Lamprey, or Spotted 
Lamprey. 
Very scarce in this district. I have not myself seen it, but am 
informed by two trustworthy observers that it has been seen in 
Luss water upon several occasions ; the description given of the 
fish's appearance and actions putting the verification of the species 
beyond a doubt. 
Unlike the smaller species, the sea lamprey is migratory, 
ascending the rivers from the sea about midsummer, and spawn- 
ing in pairs, not gregariously, in July or August. 
In England this fish is highly esteemed for the table, and is in 
season from December till May. It never appears in the Scotch 
markets, as our fishermen look upon it with the utmost disgust 
and fear. 
Anguilla vulgaris, Leach, the Sharp-nosed Eel. 
This is by far the commoner of the two species frequenting the 
loch. The young ascend from the sea as Elvers, about the size 
of a darning needle, in the month of May, and we find them up 
to all sizes during the whole summer until October, when they 
disappear. What becomes of them is not certainly known, but it 
is probable that a portion of the mature eels go down at that time 
