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Hamburger and Hamilton Stage 39

HH39 (13 days).
Scales overlapping on superior surface of leg.
Major pads of phalanges covered with papillae; minor pads smooth.
Length of third toe: 9.8 0.3 mm.
Mandible and maxilla opaque (cornified) back to level of proximal edge of egg tooth.
Channel of auditory meatus visible only at posterior edge of its shallow external opening.
Length of beak (anterior angle of nostril to tip of bill): 3.5 mm.
Feather germs: Coverts of web of wing are very long tapering cones.
Note great increase in length of feather germs in major tracts.
4-5 rows of germs at edge of lower eyelid.
Opening between eyelids reduced to a thin crescent.


  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