SWALLOW TRIBE. 99 
to induce a total alienation of parental affection—a 
change, let it be remembered, which, in every ob- 
served case, has been found to proceed gradually— 
should so suddenly succeed to the extremely active 
state of the system indicated by the recent produc- 
tion of prolific eggs. The simultaneous departure 
of both sexes also, when they desert their offspring, 
which, as far as my own researches extend, appears 
to occur with great regularity, is too remarkable a 
a fact to be accounted for on a principle so 
uncertain in its operation as that maintained by Dr. 
Jenner. 
A belief represented by Dr. Fleming, in his ‘ Philo- 
sophy of Zoology,’ vol. ii. pp. 72 & 73, as prevalent 
throughout Scotland, that Swallows are sometimes 
found torpid in their nests, has, most likely, origi- 
nated in the discovery of the forsaken young of the 
Swallow and House-Martin (for both species are 
termed Swallows indiscriminately by the multitude) 
in a perishing condition or dead. 
It appears from the following passage, extracted 
from Pennant’s ‘ British Zoology,’ vol. ii. page 155, 
that the Puffin, when placed under circumstances 
similar to those which induce birds of the Swallow 
tribe to desert their offspring, sometimes abandons 
its progeny. “The first’ young (of the Puffin) are 
hatched the beginning of July. The old ones show 
vast affection towards them, and seem totally insensi- 
ble of danger in the breeding-season. If a parent is 
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