Zur Elektronenmikroskopie der Kerneinschlüsse im menschlichen Nebenhodenepithel

Zusammenfassung Es werden verschiedene Typen von Einschlußkörperchen im Karyoplasma der Epithelzellen des menschlichen Nebenhodenepithels beschrieben. Die verschieden strukturierten Kerninklusionen werden als eine Differenzierungsreihe aufgefaßt. Sie beginnt mit kleinen rundlichen Körperchen aus feinfädigem Material und führt über die Ausbildung von Anhäufungen dichter homogener Kugeln zu großen Vakuolen wechselnden Inhaltes.

---

Summary Different types of inclusion bodies are described in the karyoplasm of the epithelial cells of the human epididymis. The structural differences between these inclusions are interpreted as being indicative of consecutive stages in the process of their formation. Thus small, spherical bodies consisting of a fine fibrous material are believed to be the initial stages in the formation of the inclusion bodies whereas the dense, homogenous globules are thought to represent a later stage. Large vacuoles containing different materials are regarded as the final stage in this process of differentiation.

---

---

Herrn Professor Dr. W. Bargmann zum 60. Geburtstag gewidmet.

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Buchbesprechungen

Ohne Zusammenfassung     

Substitution of Manganese for Tomato Juice in the Cultivation of Lactic Acid Bacteria

Tomato juice was separated by chemical and physical methods into various active fractions, as measured by growth response and acid production by numerous lactic acid bacteria. Incineration of the treated extracts with little apparent loss in activity established the fact that the stimulatory component was of inorganic composition. Of the various cations tested, manganese was the only element that produced biological activity comparable to that of the original extract. Of the 71 strains of lactic acid bacteria tested, 63 strains showed a definite requirement for manganese or tomato juice.     

CYTOTAXONOMY OF TWELVE SPECIES OF HIBISCUS SECTION FURCARIA

Menzel, Margaret Y. (Florida State U., Tallahassee), and F. D. Wilson. Cytotaxonomy of twelve species of Hibiscus section Furcaria. Amer. Jour. Bot. 50(3): 262–271. Illus. 1963.—Metaphase-I chromosome numbers and pairing in 88 accessions showed that H. cannabinus, H. costatus, and H. surattensis are diploid (n = 18); and H. acetosella, H. aculeatus, H. bifurcatus, H.furcellatus, H. meeusei, H. radiatus, H. rostellatus and H. sabdariffa are tetraploid (n = 36), with similar low multivalent frequencies, hence probably allotetraploids each combining 2 well-differentiated genomes. No intraspecific variation in ploidy was found. Fertile, vigorous F₁ hybrids between H.furcellatus and H. bifurcatus showed complete chromosome pairing (n = 36), confirming a close relationship between the parents. Two African strains of H. diversifolius were octoploid (n = 72) with low multivalent frequency and hence probably contain 4 differentiated genomes. At least 4, perhaps 5 or 6, differentiated genome groups are represented in tropical Africa, and at least 2 in the American tropics.     

Production of the Milk Agent in Cultures of Mouse Mammary Carcinoma

Thin sections of tissue cultures grown from tumors of the RIII high-breast-cancer strain mice were studied in the electron microscope. These tissues contain an abundance of particles whose morphology is consistent with biophysical measurement of the milk agent. These particles, found only extracellularly in our cultures, are formed at the cell membrane. The process of formation, as reconstructed from sections, appears to include a thickening and protrusion of the cell membrane which then evolves gradually into a dense sphere and separates from the cell in much the same manner as does influenza virus. The contents of the newly formed body are later rearranged to form a nucleoid within a membranous sac.     

PALEOZOIC LYCOPSID FRUCTIFICATIONS. I. LEPIDOCARPON PETRIFACTIONS

A reinvestigation of the 4 American species of Lepidocarpon described from petrifactions and of Illiniocarpon cadyi, also described from petrifactions, shows that they are all conspecific. When they, in turn, are compared with specimens of the British petrifaction L. lomaxi, no significant differences can be demonstrated. The criteria cited as diagnostic for the American petrifaction species of Lepidocarpon were found to fail as bases of discrimination when 400 specimens of Lepidocarpon found in coal balls of Pennsylvanian age were studied. Measurements and observations made of a sample size of 136 of these 400 specimens reveal a degree of variation compatible with that of a single species. All previously described American and British petrifaction taxa fall within (or not significantly beyond) this range of variability of a single species as determined from this sample. Additional evidence concerning the 3-dimensional sporophyll structure of this one species of Lepidocarpon and the configurations obtained by certain planes of section through it have served to demonstrate that Illiniocarpon cadyi is in reality a taxon based on sectioned structures of the sporophyll of this Lepidocarpon species. Under the rules of priority, this species of Lepidocarpon and the following are assigned to Lepidocarpon lomaxi: Illiniocarpon cadyi, Lepidocarpon ioense, L. magnificum (megasporangiate form), L. crenatum and L. palmerensis. On the basis of the morphological evidence, the British petrifaction described as Lepidocarpon wildianum is also equated with L. lomaxi.