Effect of epidermal rotation on orientation of scales in the chick☆

[摘要] Morphogenesisofscalesinthechickwasinvestigatedtoclarifyfurthertherespectiverolesofthedermisandepidermis.Squaresofwholescale-formingskinfromthesuperiorsurfaceofthetarsometatarsuswereseparatedwithtrypsinintodermalandepidermalcomponents,recombinedfollowingrotationoftheepidermisthroughvaryingdegrees,grownonahostchorioallantois,andscoredforbasicshapeandorientationofscalesaswellasforthedirectionofoverlap.Thebasicshapeandorientationofscalesarenotaffectedbyepidermalreorientation;primordiaalwaysdevelopasridgestransversetotheproximodistalaxisofthedermis,regardlessoftherelativeorientationoftheepidermis.Subsequentoverlapofscales,however,isaffectedbyepidermalrotation;epidermalreorientationpriortotheappearanceofconspicuousprimordiaresultsinacorrespondingreorientationofthedirectionofoverlapofthescales.Itisconcludedthatscalesdoariseduetotheinductiveactivityofthedermis,butthatepidermishasthecapacitytomodifythedermalstimulusbydirectingtheoverlapofscales.

[学科分类] 生物科学（综合）