THE OVARIAN EGG. aio 
But the modes of reproduction are so varied, 
the changes some animals undergo during their 
growth so extraordinary, the phenomena accom- 
panying these changes so startling, that, in the 
pursuit of the subject, a new and independent 
science — that of Embryology — has grown up, 
of the utmost importance in the present state of 
our knowledge. 
The prevalent ideas respecting the reproduction 
of animals are made up from the daily observation 
of those immediately about us, in the barn-yard 
and on the farm. But the phenomena here are 
comparatively simple and easily traced. The mo- 
ment, however, we extend our observations beyond 
our cattle and fowls, and enter upon a wider field 
of investigation, we are met by the most startling 
facts. Not the least baffling of these are the dis- 
proportionate numbers of males and females in 
certain kinds of animals, their unequal develop- 
ment, as well as the extraordinary difference be- 
tween the sexes among certain species, so that 
they seem as distinct from each other as if they 
belonged to separate groups of the Animal King- 
dom. We have close at hand one of the most 
striking instances of disproportionate numbers in 
the household of the Bee, with its one fertile fe- 
male charged with the perpetuation of the whole 
community, while her innumerable sterile sister- 
hood, amid a few hundred drones, contribute to 
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