48 



MORPHOLOGY OF SPERMATOPHYTES 



tain embryos while still attached, a fact which we have been 

 able to verify in our own experience. 



IV. THE EMBRYO 



Although the embryo of Ginkgo is exceptional among Gym- 

 nosperms, and of great interest, the details of its development 







FIG. 35. Photographs of embryos of Ginkgo biloba in various stages: A, young 

 embryo; B, older stage, showing cotyledons ; (7, a still older embryo, showing sev- 

 eral young leaves ; Z>, a portion of a nearly mature embryo, with conspicuous resin 

 ducts in stem, cotyledons, and leaves ; the beaklike process supporting the remains 

 of the nucellus is still visible. 



