‘ Stwun Loach.’ 357 
be swept away. He also removes the sand whenever 
it begins to accumulate overmuch. It would seem as if 
a current of fresh water were essential to the ova, and 
that that is why the opening of the nest is so carefully 
kept from becoming choked up. After a while the 
fry come forth—the most minute creatures imagin- 
able, mere lines about half the length of the finger- 
nail. They play round the opening, and will retreat 
within if alarmed. 
Where the brook passes under a bridge of some 
size the current divides to go through several small 
arches. There is here some fall, and the stream is 
swift and bright, chafing round and bubbling over 
stones. Here the ‘miller’s thumbs’ are numerous—a 
bottom fish growing to about four inches in length, 
and with a head enormously broad and large in 
proportion to its body. They rarely rise from the 
mud or sand; they hide behind stones, their heads 
buried in the sand, but their tails in sight. Every 
now and then they change positions, swimming 
swiftly over the bottom to another spot. Their 
voracity is very great, and they often disappoint the 
angler by taking his bait. The cottage people are 
Said to eat them. 
The ‘stwun loach’—stone loach, as the lads call 
it—hides also behind and under stones, and may be 
caught by hand. These loach are apparently capri- 
cious in their habits ; certain spots abound with them, 
in others you may search the stream in vain for a 
