296 EMBRYOLOGY AND CLASSIFICATION. 
CHAPTER XVI. 
EMBRYOLOGY AND CLASSIFICATION. 
TuE investigation of the structure and gradual 
growth of the ovarian egg is so laborious that 
it will be many years before we can hope to 
have a complete picture of all its phases. The 
apparatus required for the task is very compli- 
cated, and a long training is necessary merely 
to prepare the student for the use of his instru- 
ments. <A superficial familiarity with the mi- 
croscope gives no idea of the exhausting kind 
of labor which the naturalist must undergo 
who would make an intimate microscopic study 
of these minute living spheres. The glance at 
the moon, or at Jupiter’s satellites, which the 
chance visitor at an observatory is allowed to 
take through the gigantic telescope, reveals to 
him nothing of the intense concentrated watch- 
ing by which the observer wins his higher re- 
ward. The nightly vision of the astronomer, 
revealing myriad worlds in the vague nebulous 
spaces of heaven, is not for him; he must take 
the great results of astronomy for granted, since 
