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Hamburger and Hamilton Stage 37

HH37 (11 days).
Claws of toes flattened laterally and curved ventrally, dorsal tips opaque.
Tip of claw on wing opaque.
Pads on plantar surface of foot conspicuous and smooth.
Transverse ridges along superior surfaces of metatarsus and phalanges (future scales).
Length of third toe: 7.4 0.3 mm.
Labial groove on mandible is clearly marked off.
Comb clearly serrated.
Beak (from anterior angle of nostril to tip of bill) = 3.0 mm.
Feather germs: much more numerous, and in most advanced tracts (e.g. back, tail) elongated into long, tapered cones.
External auditory meatus nearly surrounded by feather germs.
Circumference of eyelids bordered by single row of just-visible primordia; none on remainder of lids.
Sternal tracts contain 5-6 prominent rows when counted at anterior end of sternum.
Nictitating membrane has reached anterior edge of cornea.
Upper lid has reached dorsal edge of cornea.
Lower lid has covered 1/3-1/2 of cornea.


  1. TXT - Text Format
    The ABSTRACT ONTOLOGY (NOT Staged/Timed) with all pathways to child nodes materialised, in Plain Text only, as a Tree Report.

  2. OBO - OBO Format
    The ABSTRACT ONTOLOGY (NOT Staged/Timed) in OBO Flat File Format, version 1.2, available for viewing/editing using OBO-Edit.


  1. H. Eyal-Giladi and S. Kochav
    From cleavage to primitive streak formation: A complementary normal table and a new look at the first stages of the development of the chick : I. General morphology
    Developmental Biology, Volume 49, Issue 2, April 1976, Pages 321-337

  2. V. Hamburger and H.L. Hamilton
    A series of normal stages in the development of the chick embryo
    Journal of Morphology, 1951, Volume 88, Pages 49-92 (reprinted in Developmental Dynamics, December 1992, Volume 195, Issue 4, pages 231-72)

  3. R. Bellairs and M. Osmond
    The Atlas of Chick Development
    Academic Press, ISBN 0-12-084790-6, 1998

  4. C.D. Stern and P.W.H. Holland (Ed.s)
    Essential Developmental Biology: A Practical Approach
    Oxford University Press, ISBN 0-19-963423-8, 1993

  5. M.A.J. Selleck and C.D. Stern
    Fate mapping and cell lineage analysis of Hensen's node in the chick embryo
    Development, Volume 112, Pages 615-626, 1991