NATURE 613 
re) 
and rocking from side to side as they appear to 
discuss the matter in raucous tones. © Gradually 
they become calmer, until finally the matter is 
Fic. 2.—An adélie penguin sitting on eggs. 
settled and they have pledged their faith for the 
rest of the season. 
Once made the compact is final, and though, 
unhappily, death from misadventure breaks up 
many a home, those that survive 
remain unswervingly faithful to 
one another. Overtures are fre- 
quently made by unmated cocks 
to mated hens during the. early 
part of the year, before the eggs 
have come, but the husband takes 
good care of his wife, and soon 
drives off the interloper. 
The pair being wedded, the 
cock fetches stones for the nest, 
which the hen builds. A week 
or so elapses and the first egg 
is laid. In two or three days’ 
time the second appears. Up to 
this time none of the birds at- 
tempt to get food, but when the 
eggs are both laid one of the pair 
goes off to the nearest open 
water, and may remain away a 
week or ten days, after which it 
returns and takes its turn on the 
eggs (Fig. 2), whilst the . other 
goes off for a similar period to 
catch the little shrimp-like crus- 
tacea that abound in the Ant- 
arctic seas, and to gambol with 
groups of neighbours in_ the 
water and on the sea ice. 
The eggs take about thirty- 
two days to incubate, and at the 
end of this time the little plush- 
coated chicks appear all over the 
rookery. These grow at a great 
rate, eating voraciously. Some 
idea of their rapid growth may be got from the 
photograph showing a chick twelve days old 
(Fig. 3). 
Won 2337, VOL. ge 
_ Now the adult birds are extremely fond of play- 
ing games, and spend whole days in playfully 
skirmishing with one another on the sea-ice near 
the rockery, and having rides on the ice floes that 
drift past on the tide. Consequently, the needs 
of the youngsters becoming greater as they grow 
bigger, when these are about a fortnight old an 
ingenious social arrangement is made by the 
entire rookery, resulting in a great economy of 
labour. Hitherto, the greatest care has been 
taken by the parents to prevent the chicks from 
straying away from the nests, hecause when they 
do so they are invariably pounced upon by the 
skua gulls which are always in attendance to prey 
upon them, and should the chicks seek the protec- 
tion of neighbours the latter would only drive 
them away with savage pecks which might prove 
mortal to the tender youngsters. 
Now, however, by mutual consent all this is 
changed, and the occupants of large groups of nests 
(Fig. 4) pool their chicks so as to form créches, 
sometimes consisting of many dozens of young- 
sters, which are guarded by a few old birds who 
take turns to remain on duty whilst the rest are 
free to go off to get food and to play. The sentry 
birds take good care of the créches under their 
Fic. 3.—A chick twelve days old. 
charge, and soon drive in any of the chicks that 
try to get away, so that these learn to keep in a 
cluster and are safe from the attacks of the skuas. 
