NATURAL HISTORY OF BRITISH SALMONIDZ. 139 
The female, regardless of the frequent absences of her lord 
during his internecine contests, and probably satisfied with 
the presence of the male parr, proceeds quietly with her opera- 
tions by throwing herself at intervals of a few minutes, upon 
her side, and whilst in this position, by a rapid action of the 
tail, she digs a receptacle for her eggs, a portion of which 
she on each occasion deposits, and, again turning on her side, 
covers it up by a renewed action of the tail—thus alter- 
nately digging, depositing, and covering over until the whole 
are laid. 
The adult fish after spawning are called ‘spent’ or unclean 
fish, or ‘kelts ;’ and at this time they are quite unfit for food 
—indeed almost poisonous—and their capture is prohibited by 
law. Lately spawned kelts may be recognised by their dark 
unhealthy colour, lanky flaccid appearance, and by the enlarge- 
ment of the vent. ‘Their gills also are almost invariably found 
to be infested by a species of white worm, the Lernea salmonis 
of Linnzeus, often improperly called a maggot, from which they 
are released by contact with the salt water—a similar release 
from other parasites being obtained on passing to the fresh 
water from the sea. 
For some time after spawning, however, they are in a very 
weak and exhausted state, and have not energy for immediately 
descending the river. Accordingly they usually drop down from 
the spawning grounds, or ‘redds,’ to the first quiet deep, there 
remaining until their strength is recruited. They then con- 
tinue falling back with the winter and spring floods, descending 
from pool to pool, and avoiding as much as possible weirs and 
rapid currents, until they reach the sea. Here they quickly 
recover their condition, to ascend the rivers again (in at least 
many cases) in the autumn or succeeding spring for the same 
purpose as before, but almost always remaining some time in 
the brackish water or tideway before making either decided 
change. 
Within a period of five or six months after their return from 
the salt water, it has been proved that at least a proportion of 
