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 ...

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 ...

The four species of lampreys native to the upper Great Lakes (American brook lamprey, Lampetra lamotteni; chestnut lamprey, Ichthyomyzon castaneus; northern brook lamprey, I. fossor; and silver ...

"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 SCDIRB copy 39088019622893 not included in the Bibliotheca Beckwithiana (unpublished).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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