Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / The histology, histochemistry arxi fine structure of the tubular glands of the isthmus region of the hen's oviduct were studied during various phases of the egg laying cycle. Numerous tubular glands were found in the lamina. propria of the isthmus region. These glands consisted of a single layer of pyramidal epithelial cells. Histochemical studies showed the presence of large secretory granules in the apical region of the cytoplasm of the gland cells. 'lhese granules were composed of neutral mucopolysaccharides and sul:fur-ccmtaining proteins and were especially abundant during active secretory phases of the egg laying cycle. [TRUNCATED] / 2031-01-01