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Zustand: New. In French.

Hemispheric-apex cells (HC), which are situated at the intersection of the three branches of Hoyle's organ in Loligo vulgaris and Loligo forbesi embryos, were investigated using light- and transmission-electron microscopy. The surface membrane of the HC exhibits many microvilli. Desmosomes between HC were distributed in patches along the plasma membrane. These desmosomes were also found between HC and the hatching enzyme producing cells of Hoyle's organ (CHO) and between neighbouring CHO. The area below the most apical desmosomes shows many cellular interdigitations. One (or several) small Golgi apparatus and many mitochondria were found in the cell centre. Mitochondria were also abundant in the most apical part of the cell. In the HC the nucleus is situated near the cell centre. The cell shape of the central part of the cell usually corresponds grossly to the nuclear form. Endoplasmic reticulum was found near the nucleus and in the lowermost part of the cell, but is never as abundant as in the CHO. In the most apical part of the HC many oval vesicles were found containing electron lucent material. Sagittal ultrathin sections showed that the tapering proximal part of the HC, directed toward the underlying tissue may end in a T-shaped form. As the HC and CHO degenerate after hatching, it is concluded that both structures are transient embryonic cells. 10 pp., 7 figs, 4.

The mantle epithelium of embryos and early juveniles of the squids Loligo vulgaris and Loligo forbesi and the cuttlefish Sepia officinalis was studied using scanning electron microscopy. In embryos of L. vulgaris and L. forbesi, previously undescribed epidermal structures were found. They are missing in S. officinalis embryos. These so-called "extruding structures" are located near Hoyle's organ and first appear at stage XIII of Naef. At the same embryonic stage, Hoyle's organ starts to differentiate and "uniform-type" ciliated cells become visible in the epidermis of both L. vulgaris and L. forbesi. Directly after hatching the epidermis of the species examined starts to slough off and finally the extruding structures, Hoyle's organ and both types of ciliated cells of the mantle epithelium disappear. The function of the extruding structures remains obscure. 9 pp., 6 figs, 4.

8 pp., 3 figs, 4.

Couverture souple. Zustand: bon. ROD0009878: 1883. In-12. Broché. Etat passable, Tâchée, Mors arrachés, Mouillures. 645 pages, quelques rousseurs, gravures n&b. 103 figures intercalées dans le texte - dos cassé - PHOTO DISPONIBLE. . . . Classification Dewey : 616.6-Maladies génito-urinaires.

Antwerpen, published on the orders of the municipality, 1864 - 1934, in-8°, first published as three-monthly issues, later as a yearbook, pagination runs through for the whole year. Bound in nearly uniform half cloth, with boards covered in marbled paper, title and volume numbering on smooth spine. Due to the poor quality of the endpapers the title page and the last leaves of the first 7 volumes are browned and/or stained. AVAILABLE: Series 1 : 1864 ( tome premier ) -> 1893( tome trentième ) ; Series 2 : 1926 (first year ) -> 1934 (ninth year). Complete set of this periodical which aimed to publish important sources of the very rich municipal archives. Antwerp was in the 16th c. one of the most important European towns north of the Alps . It became also the centre of the struggle between Catholicism and Protestantism. Among the published source texts : Index on the ordinances ( 1489 - 1650). Inheritance of Rubens. Ordinances on religeous disputes ( ca. 1600 pp ). Collegiale actenboeken (starting in 1583.) (ca. 4000 pp ). Charges against persons in religious matters ( ca. 3500 pp, indexed). Establisment of glass factories. Bochius '' Epistolae publicae ''. Register of writs (starts in 1450, ca. 1500 pp).These texts have never been reprinted.