The anatomical record . ate cells differentiatinginto feather l>arl)ules are shown with their cytoplasm packed with melaningranules received from mclanophorcs. .\l the left, histological details have beenndihil with a pen. a camera lucitla being employed. (>c. 10; obj. mm. i Hausch A- Lombi. The picture was much reduced in barb-vane ridgi appears cotnplctcly, another at the left is almost all in thepicture, and a large portion of a third at the right is included. germ sections, according to Mrs. Knowlton. In all cases thepigmented inner .sheath cells we
The anatomical record . ate cells differentiatinginto feather l>arl)ules are shown with their cytoplasm packed with melaningranules received from mclanophorcs. .\l the left, histological details have beenndihil with a pen. a camera lucitla being employed. (>c. 10; obj. mm. i Hausch A- Lombi. The picture was much reduced in barb-vane ridgi appears cotnplctcly, another at the left is almost all in thepicture, and a large portion of a third at the right is included. germ sections, according to Mrs. Knowlton. In all cases thepigmented inner .sheath cells were found within the first mil-limeter from the inferior uml)ilicus, , at the proximal endof the feather germ, but not in every section of this pigmentation was irregular and sjjarse. The granules wereof the same size, form, and color as those of the intermediateand cylinder cells. The melanin granules were found usually on the outer or periph-eral side of the nucleus, as in the case of pigmented cylinder. MELANIN IKiMKNT I.\ KKATHKK (iEUMS 103 cells. As there wore no mclaiioplioros near crKHinh t havedistributed niclaiiiii niaimlis to these cells, we eoiiehjded that theyalso must have a capacity for forming melanin granules. Suchcells never accumulate many Kranules. ami they always retaintlieir normnl character as stratified s(|uaiiHiiis e])ithelium. B. Origin of dermal pulp pigment Melaiiopliores were found at tlie i)roximal end ot the dermalpulp near the inferior umbilicus of feather germs from both thePlymouth Rock and Brown Lcfrhorn fowls (figs. 1, 3, and 4).Dermal pulji pigment was not found in the feather germs of overten species of birds previously studied by me, and 1 know of noother ol)sci\ations of it, Ral)l (94) found no melanin pigmentin the dermal pulp of nestling-down feather germs from thechick. The dcinial iii(lan()])hores we observed occurred in the mesen-chyma not far from the membrane, as may be seen infigiUTs 1, ) and (>. Usually
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectanatomy, bookyear1906
