A BIRD’S EGG 207 
but for the strong, roundish shape of the egg, would be 
attended with considerable risk. 
(4) But few birds lay spherical eggs, the great majority 
of eggs being ovoid in shape-—the form best suited for packing 
into a circular nest. This can readily be brought home to 
children by drawing a circle, dividing it into a number of 
sectors, and discovering ‘by trial the shape which most 
completely fills each compartment. The eggs in an 
ordinary nest will be: 
found on inspection 
to be packed with 
their small ends. 
pointing towards the 
centre. 
(5) It follows from 
par. (4) that since 
roundish eggs can 
be closely packed 
together, the round- 
ish or ovoid shape is. 
the one which en- 
ables the bird to 
Fig. Pi Diner RRO Deel ae of eggs cover her eggs most 
completely. 
(6) If an attempt be made to roll a carrot or other cone- 
shaped body across a table, the difficulty of doing so will 
at once be seen. ‘The object, instead of rolling along in 
some definite direction, will turn round the apex as though 
this point were fixed. A modified form of the same result 
can be obtained by using a typically shaped ege—unless 
pushed with considerable violence, there will be some 
difficulty in getting it to roll in a straight line. Conical 
egos are usually laid in flat, open nests, exposed to the wind, 
and, but for the protection afforded by their shape, would be 
