All vertebrate embryos follow a common developmental path due to their common ancestry. All have a set of very similar genes (the homeobox genes) that define their basic body plan. As they grow, the ...

IN the rapidly-shifting condition of our knowledge of the development of all kinds of animals, it is a most difficult thing to produce a satisfactory treatise on Comparative Embryology. None the less ...

IT is generally acknowledged that land-living plants have sprung from some algal source: that the land was invaded and that the invaders show form and structure adapted to sub-aerial life. If this be ...

"With 2057 drawings and photographs, grouped as 380 illustrations." SCDIRB copy 39088019622893 not included in the Bibliotheca Beckwithiana (unpublished). SCDIRB copy has bookplate: Smithsonian ...

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