The treatment of observations in early astronomy

Communicated by Curtis Wilson     

On the expansion-contraction rhythm of the sea anemone,Actinia equina L.

Riassunto È stato studiato il ritmo di espansione-contrazione di esemplari diActinia equina L. della zona interoctidale del Mar Tirreno, sottoposti a condizioni differenti di illuminazione e di livello d'acqua. Gli autori ritengono che il ritmo sia direttamente dipendente dall'illuminazione ambientale e dallo stato di copertura o scopertura conseguente alle maree. Una luce di intensità pari a quella lunare non esercita alcuna influenza sul ritmo.

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Research supported with a grant of the Consiglio Nazionale delle Richerche.     

On the presence of an external hemal pore inLymnaea stagnalis L.

Zusammenfassung Lymnaea stagnalis verliert nach starker Reizung Blut aus einem der Nierenöffnung dicht anliegenden hämalen Porus, der in Verbindung mit dem System der Blutsinusse steht.     

Biosynthesis of alkaloids. On the occurrence of keto acids inPapaver somniferum L. Plants

Zusammenfassung BeiPapaver somniferum L. wurde im Laufe der Ontogenese die Anwesenheit von Ketosäuren des Zitronensäurecyclus verfolgt. Zur Blütezeit und nach dem Verblühen konnten auch die aromatischen Ketosäuren, Phenylbrenztraubensäure undp-Hydroxyphenylbrenztraubensäure nachgewiesen werden (2,4-Dinitrophenylhydrazone und nach Reduktion zu Aminosäuren: Phenylalanin und Tyrosin).     

Some observations on bipolar filaments formed by non-muscle myosins.

Adrenal medullary and retinal myosins formed bipolar filaments in vitro. These filaments showed features suggesting flexibility in the rod region of the myosin molecules composing such filaments; in certain cases the myosin heads spread away from the filament backbone, in others the backbone itself was twisted. In addition the bare central backbone showed transverse striations.     

On the innervation of the prothoracic glands inPapilio demoleus L. (Lepidoptera)

Zusammenfassung Die Prothorakaldrüse der SchmetterlingsraupePapilio demoleus L. ist mit Sicherheit innerviert, wobei jede einzelne Drüsenzelle von Nervenendigungen umsponnen ist. Der Befund spricht für eine Aktivierung der Häutungsdrüse durch Neurosekret, das durch Nerven zugeführt wird.     

Resolution of singularities of surfaces by P. Del Pezzo. A mathematical controversy with C. Segre

We examine in some detail a series of papers published by P. Del Pezzo and C. Segre on the resolution of singularities of algebraic surfaces, trying to point out the main ideas.In 1888 P. Del Pezzo published a proof of the resolution of singularities of algebraic surfaces using birational transformations. He introduced the notion of equisingularity of two surfaces at a point or along a curve. This notion is made specific in a paper of 1889. C. Segre in his famous paper on infinitely near multiple points on a surface published in 1896 shows that Del Pezzo's method does not always produce a smooth surface. During 1897 each author reasserts his point of view in several papers which contain interesting remarks, regardless of their increasingly polemic style.     

Some observations on the Rohon-Beard cell perikaryon.

During the hatching period, the Rohon-Beard cells of Salmo gairdneri showed definite structural maturity of their perikarya, which is in contrast to the amphibian species investigated, where neuronal maturation of the Rohon-Beard cells is finished only in later -- posthatching -- developmental stages.     

On the pathogenesis of intestinal aganglionosis. A consideration based on electron microscopic observations of experimental and clinical aganglionoses

Summary A close resemblance in fine structure was observed between the aganglionic colon, produced in rats by serosal application of 0.1% benzalkonium chloride solution, and the aganglionic descending colon, or more proximal segments, of Hirschsprung's disease. The pathogenesis of the disease is discussed.     

Some observations on carotenoid synthesis by the algaChlorella vulgaris

Zusammenfassung WirdChlorella vulgaris in einem Medium, das Glukose, Pepton und Mineralsalze enthält, gezüchtet, so synthetisiert sie sowohl in Licht wie im Dunkeln -Carotin, Lutein, Violaxanthin und Neoxanthin. Das Wachstum im Dunkeln beträgt jedoch nur 1/6 von demjenigen im Licht. Die Carotinoide verschwinden aus alten Lichtkulturen, werden aber in alten Dunkelkulturen weiter synthetisiert. Diphenylamin hemmt das Wachstum dieses Organismus bei einer Konzentration von 1/280 000 vollständig.