38 Fish Cultural Assoctation. 
than that preferred in summer, as well as other important 
changes in respect to specific gravity and pressure. 
The hybernation theory is a favorite one with the fisher- 
men of the British provinces, and has recently received strong 
support from Professor Hind in his treatise on the “ Fisheries 
of North ‘America.’ , His arguments’refer to the mackerel, 
although the scup, tautog, and herring are included by impli- 
cation. He refers to the appearance of the mackerel “with 
scales on their eyes, and blind,” and suggests. that the winter 
sleep of fishes is probably much more general than is usually 
supposed. He takes the position that there are only two al- 
ternatives possibly open to fishes which cannot live in cold 
water. They must migrate south or hybernate. His argu- 
ments naturally fall into two catégories—those against migra- 
tion and those in favor of hybernation. Those in favor of 
hybernation may be summed up as, first, the testimony of 
fisherman and travellers; second, the quoted opinions of theo- 
rizers; third, the alleged hybernation of other fishes; and 
fourth, peculiarities in early and late fishes. 
(1.) The statements of one M. Pleville le Peley, “an eye- 
witness,” are quoted both from Lacepede and H. de la Blan- 
chere. Male Peley gravely states that he had observed about 
the coasts of Hudson Bay “the mud at the bottom of the 
small, clear hollows, encrusted with ice around their coast, 
entirely bristled over by the tails of mackerel imbedded in it 
nearly three parts of their length ;”* and again “affirms hav- 
ing seen in the middle of winter, in deep, muddy bottoms, 
myriads of mackerel packed one against the other, with one- 
half the body plunged in the mud, where they remained 
during the winter. As soon as spring came they aroused 
themselves from their torpor and appeared always on the 
* Hind, op. cit, Part II., p. 10, note. 
