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The paper describes the variation pattern of magnetic susceptibility of Lameta sediments and isotopic variation of organic13C from Chui Hill, Bergi, Kholdoda, Pisdura and Girad. The susceptibility pattern and a negative carbon isotopic anomaly allows fixation of the K/T boundary at these localities and they differ in these aspects from the inter-trappean sediments at Anjar.

Reactions of 1,2,5,6,8,10-hexamethylheptalene (1) and its bond isomer, 1,4,5,6,8,10-hexamethylheptalene (2), with tricarbonylchromium complexes L{in3}Cr(CO){in3} (L=NH{in3} and Py) have been investigated. Thermodynamically less stable complex 1 exhibits higher reactivity with respect to Py{in3}Cr(CO){in3}/BF{in3} · Et{in2}O under the conditions of Ofele's reaction than complex2. At 10–30 °C, the Cr(CO){in3} group is coordinated to the asymmetrically substituted ring, which is accomplished by the shift of double bonds in the ligand, to afford tricarbonyl-[1,4,5,6,8,10-hexamethyl-η{su6}-(10a, 1–5)heptalene]-chromium (6) as the only mononuclear complex. Under more drastic conditions (Raush's reaction, 80 °C),1 ↔ 2 interconversion proceeds faster than the reaction of individual bond isomers with coordinatively unsaturated “hot” particles (solv){inn}Cr(CO){in3}. In this case, all of the four possible isomeric mononuclear complexes (6–9) and two binuclear complexes (10 and 11) are formed. The structures of complexes 6–11 have been studied by NMR and mass spectrometry, the structure of6 has been established by X-ray diffraction analysis. Heating a solution of6 in octane at 115 °C results in the isomerization of6 into complex7 through the intracycle 1,2-shift of the Cr(CO){in3} group and also in its conversion into complex8, which is the first example of interring η{su6}→η{su6}-haptotropic rearrangement in nonplanar seven-membered π-systems.

Clusters of mitochondria have been observed close to the inner end of the pores in Nonionella stella, Globobulimina pacifica, Buliminella tenuata, Bolivina argentea, Loxostomum pseudobeyrichi, Cassidulinoides cornuta and Bolivina cf. subexcavata, pointing to a pore function of oxygen-uptake. The relationship between mitochondria and pores is most distinct in Buliminella tenuata, Bolivina argentea and L. pseudobeyrichi collected from a deep-water, low-oxygen environment. Amphistegina lobifera Larsen, 1976 readily took up 14CO2 through its pores, indicating a pore function related to the photosynthetic activities of its symbionts. 14C-labelled glucose did not pass through the pores in traceable amounts during a 2 h exposure time.

The metallurgical significance of the magnetic hardness test is a matter that will require considerably more study and development before the facts are better known and better understood. At this stage of development, however, the magnetic hardness characteristics appear definitely to be related to one of the properties in the steel, at least, which contributes to the physical hardness, and there are indications that correlations also exist with other properties of the steel.

I BEG permission to acknowledge the receipt of the open letter sent me through your Journal of March 10, by the leading zoologists of Great Britain and Ireland, regarding my resignation from the Copenhagen Museum and my zoological investigations. I am deeply conscious of the great honour done me in sending me such an address, and I regret that I am unable to write to all personally; but for that reason I would request them through your columns to accept my most sincere and heartfelt thanks.