Indipendenza della differenziazione istologica e della morfogenesi del cristallino

Zusammenfassung Verfasser berichtet über die abnormale Entwicklung der Linse eines Hühnerembryos, bei dem im Stadium von 10 Urwirbeln Mittelhirn und Rautenhirnanlagen entfernt wurden. Infolge eines ausgedehnten Blutergusses wurde die Morphogenese des Augenbechers und des anliegenden lentogenen Ektoderms gestört. Die Einstülpung des präsumptiven lentogenen Ektoderms fiel aus und an Stelle der Linse bildete sich eine scheibenförmige Verdickung des präsumptiven lentogenen Ektoderms. In der Mitte bestand diese aus sehr hohen prismatischen Zellen, die sich unter allmählicher Abnahme der Zellhöhe in die niedrigen Zellen des Hautektoderms fortsetzten. Verfasser erblickt darin ein Beispiel von Aufhebung des Zusammenhanges zwischen Morphogenese der Linse und Differenzierung der sie bildenden Zellen. Infolge der besonderen örtlichen mechanischen Bedingungen verblieben die Zellelemente, die zur Umwandlung in Linsenzellen bestimmt waren, an der Oberfläche im Zusammenhang mit dem Deckepithel, die gleichen Bedingungen schufen einen allmählichen Formübergang zwischen den Zellen, die den Linsenfasern ähnliche Merkmale zeigten, und jenen, welche das vordere Linsenepithel bilden sollten.     

Riconoscimento e Dosamento della Psilocibina

It is possible to detect and dose Psylocibine, a psychoneurotropic substance occurring inPsilocybe, Stropharia, Panaeolus etc., with a reaction already used to detect Tryptophane and indole-auxins (6) (7) (8) (9). This method is more sensitive than U.V. measurement and Keller's reaction (4) (see fig. 3). Optical density is proportional to concentration from 0,005 to 0,050µmoles per ml when measured in a 1 cm cell in the Beckman spectrophotometer. Tryptophane, indole-auxins and 2-deoxy-sugars could interfere (6) (7) (8) (9) (10). procedure: In a test tube are pipetted:

1. 1 % solution of fructose in H₂O : ml 0.1
2. 5 % solution of cysteine hydrochloride : ml 0.2
3. methanolic solution to be tested : ml 1.0
4. conc. H₂SO₄/water 70/30 (v.v.) : ml 3.0 the mixture is allowed to cool off at room temperature, a pink color develops and reaches its maximum of intensity in about 90 minutes.

The absorption spectrum of the chromophore exhibits a maximum at 512 mµ (see fig. 2). The ratio E₅₁₂ in the reaction mixture/E₂₆₇ in U.V. is about 1,9 and differs from other indole-derivatives. (see Tab. II). The reaction can also be employed to detect and dose Psylocibine-spots in paper and thin-layer chromatography spraying with the following mixture prepared just before use: fructose g 1.0 cysteine hydrochloride g 1.0 3 N H₂SO₄ ml 100 Paper — chromatograms are dried in an oven (70°C) for 5 minutes, chromatoplates for 10–15 minutes. Psylocibine appears as a pink spot.     

Cenni illustrativi della geologia,geomorfologia e pedologia della Basilicata

Abstract

On the basis of recent researches the main outlines of the Lucania geology are briefly discussed. The more typical landscapes of this region are then delineated, from that of the calcareous dolomitic mountains to those of the flysch, of the marine pliocene sediments, of the volcanic area (Vulture) and the marine and fluviatile pleistocene terraces of the metapontian littoral. The principal evolution trends of the pedogenesis are finally illustrated with some reflection on the very difficult problems of the soil conservation in this area.     

Lineamenti agronomici e selvicolturali della Lucania

Abstract

Agro-sylvicultural aspects of Lucania. In the Basilicata Region one can find many types of natural habitats from the mediterranean « macchia » to the rocky peaks of Monte Pollino. Natural environmental factors greatly condition land utilization and sub-spontaneous plant formations such as forests, opens scrubs, and grazing lands, occupy 49% of the productive land (53% in the Province of Potenza alone): this is a high figure as compared to the one for the whole of southern Italy (37.5%). Forested land is 18% of the total and also this value is higher than the corresponding one for the whole of southern Italy (14.4%). Cereals are the main crops: the economy of Basilicata is therefore mainly based on pastoral-cereals growing activities.

The regional flora is very interesting including as it does several relict and endemic species. The most precious jewel for nature lovers is the over 6000 feet high, richly forested, massif of Pollino where one can find some of the few Italian stands of Pinus leucodermis, and, among the animals, the extremely rare Gypaëtns barbatus, besides what is probably the only Italian autoctonous roe-deer population.

The conservation of so many naturalistic riches does not necessarily clash with the regional economic development.     

Contributo allo Studio Floristico e Fitogeografico degli alti Pascoli della Montagna della Duchessa

Summary

After having summarily described the ecological conditions of the «Montagna della Duchessa» the author lists the plants collected in this area by him and earlier by Martelli and Anzalone. Notes on the geographical distribution of some species in the most important mountains of Central Italy and critical remarks on the taxonomy of some plants are added to the list. Some taxa must be regarded as having been found for the first time in the Abruzzi.

On the basis of the biological spectrum and of the percentage of the geographical elements, the author takes into account the ecological and phytogeographical features of this flora and points out its affinity with the flora of the lands with an arctic climate.

The author describes the commonest plant-communities, by means of statistical investigations, lists of plants with frequency of each taxa, and field notes. Finally he takes into consideration some peculiar features of the flora of this area.     

Istogenesi e differenziazione dei neuroni e degli elementi gliali della corteccia cerebrale

Zusammenfassung Vorliegende Untersuchungen bezwecken, die Histogenese der Groß-hirnrinde beim Schafe von den frühesten Stadien der Differenzierung der Neuronen und der Gliazellen ab durch die Golgische Chromsilbermethode zu erforschen. Ferner wurden die Änderungen in der Form der Neuronen und der Gliazellen in späteren Stadien der Entwicklung bis zur Geburt verfolgt. Die Beobachtung von His, daß bipolare Neuroblasten von der Keimschicht gegen die Oberfläche der Rinde wandern, wurde bestätigt. Die bipolaren Neuroblasten sammeln sich in der kompakten sog. 'Bil-Dungszone (Koelliker), wo sie sich schon in frühen Stadien der Entwicklung mit der Chromsilbermethode färben. Der obere plumpere Fortsatz der bipolaren Neuroblasten wird zu einem Dendrit (dem Spitzenfortsatz der reiferen Pyramidenzelle), der untere gegen die Keimschicht gerichtete Fortsatz wird zum Neuriten. Die sog. Bildungszone wird durch Einwanderung von Neuroblasten von der Tiefe allmählich dicker; bald differenzieren sich die oberflächlichsten Neuroblasten weiter und wandern in entgegengesetzter Richtung, d. h. gegen die tieferen Schichten, wo sie in verschiedener Höhe stehenbleiben und das charakteristische Gepräge der Pyramidenzellen annehmen. Gleichzeitig fährt die Wanderung von Ganglienzellen von der Tiefe gegen die Oberfläche der Rinde fort. Dieser Vorgang vollzieht sich während der ganzen fetalen Entwicklung und sogar nach der Geburt, wenn die mittlere Schicht eine beträchtliche Dicke erworben hat. Dadurch wird die Zahl der Neuronen bis in späten Perioden des Wachstums allmählich größer. Die Differenzierung der Ganglienzellen, welche in späten Stadien wandern, wenn sogar die weiße Substanz eine beträchtliche Dicke erreicht hat, fährt fort. Die Zellen gewinnen die Merkmale der reifen Zellen (lange Dendriten, Tigroidschollen im Cytoplasma) lange bevor sie ihre definitive Lage erreicht haben. Diese Zellen werden zu den polymorphen Zellen der fertigen Hirnrinde.Die Stützsubstanz der embryonalen Hirnwand besteht ausschließlich aus Fortsätzen der Ependymzellen. Diese bilden sich nur bei dem 250 mm langen Schaffetus zurück. Die Gliazellen erscheinen lange bevor die Fortsätze der Ependymzellen verschwinden, in verschiedenen Höhen der Hirnwand, in der Bildungszone und in der intermediären Schicht. Die Gliazellen sind in der fetalen Rinde mit zahlreichen, feinen Fortsätzen versehen, die ihnen ein besonderes, von dem der reifen Gliazellen verschiedenes Gepräge verleihen. Beim Fortschreiten der Entwicklung unterliegen sie einer tiefen Umwandlung dergestalt, daß neue, ganz verschieden aussehende Fortsätze an Stelle der fetalen erscheinen. Vor der Geburt ähneln sie stark den protoplasmatischen Astrocyten. Die beobachteten Umwandlungen sollen als Ausdruck der ameboiden Tätigkeit der Gliazelle gedeutet werden.Meinen Beobachtungen nach stammt nur ein Teil der Gliazellen von umgewandelten Ependymzellen ab, welche sich aus ihrer ursprünglich tiefen Lage nach der Oberfläche verschoben haben. Andere Gliazellen gehen aus Spongioblasten hervor, d. h. aus Zellen, welche ihren Ursprung direkt aus der Keimschicht nehmen, als scheinbar undifferenzierte Zellen durch die Hirnwand wandern und sich später zu Gliazellen differenzieren [Schaper (1897), Lenhossék (1891)].

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Alle presenti ricerohe ha contribuito il C.N.R.     

Differenziamento biochimico della parete in Angiosperme e Gimnosperme

Abstract

Biochemical changes in Angiosperms and Gymnosperms cell-walls during cellular differentiation in xylem. - During differentiation of the vascular cambium in xylem cells there are changes on the biosynthesis of cell-wall polysaccharides in angiosperms and gymnosperms. Pectins are synthesized during primary growth only, whereas the synthesis of hemicelluloses and cellulose increases markedly during secondary thickening; simultaneously the synthesis of lignin begins. The cells can modulate the synthesis of cell-wall polysaccharides by an induction and repression or an activation and inactivation of certain key enzymes. It has been shown that the major control operating during xylem differentiation is exerted on polysaccharide synthases. Further controls are envisaged on the transport of nucleoside diphosphate sugars from the cytoplasmic pool to the endomembrane, on the transport of neoformed polysaccharides through the endomembrane flow, and at plasmalemma level. It has also been emphasized the role of cell-wall in autoregulating its growth and differentiation.     

L'Influenza Delle Condizioni Fotoperiodiche e Termiche Sull'Accrescimento e Riproduzione della Salvia Longistyla Benth

Summary

Observations on growth and development of Salvia longistyla Benth., in several photoperiodic and termoperiodic conditions, both natural and artificial, were performed. The conclusions of my work are the following

I° - It has been proved that Salvia longistyla is a typical short-day plant and that its critical point of reaction lies approssimately on the 14 hours, when the average night-temperature is about 18°C; the flowering does not succeed if the night-temperature is decidedly below 15°C.

II° - The plant' requires short-day conditions not only for the formation of the flower buds, but also for the subsequent development, i. e. the full bloom; consequently the plant belongs to Eguchi's S. S. class (short day-plant for both the manifestations).

III. - Under natural conditions, in our latitude, Salvia longistyla flowers only in Autumn, because only in this season we have suitable photoperiod and concomitantly suitable night-temperature. In Spring, though the day is short, the night-temperature is not sufficiently high; in Winter and in Spring, the flowering is possible only in a warm green-house, with a night-temperature of about 18°C. In orange green-houses Salvia longistyla can continue the flowering begun in Autumn; during Winter and Spring new blooms do not succeed, just because the night-temperature, in such green houses, is never sufficiently high.

IV. - We can obtain fruiting only by artificial pollination (lack of natural pollination agency).

V. - The basal branches do not flower even in optimal photo- and termoperiodical conditions (which allow apical flowering) on acount of a mechanism of correlative inhibition.

VI. - The elongation of the internodes is relatively inhibited at a very long photoperiod, differently from what we observe in most plants.

These prerogatives, verified in repeated experiments, are in perfect accordance with the characteristics of the ambient in which the plant is naturally diffused (Mexico). The altitude and latitude of the stations in which the plant has usually been found, have a short photoperiod all year long, and temperatures (also night-temperatures) costantly suitable for a good growth and bloom. The plants, in the natural ambient, are perennial and bushy. The pluri-annuality can be referred to the flowering inhibition of the lateral and basal branches, that takes place in a specimen and that keeps on for a long time, also after the full flowering of the principal axis. The basal shoots show a tendency to the vegetative growth, even though the external conditions are suitable to the flowering of the apical parts of the plant. Therefore we must attribute the pluriannuality of S. longistyla to this correlative flower-inhibiting mechanism.     

Studio Floristico e Fitogeografico Delle Piccole Isole della Sardegna Nord-Occidentale

Summary

The author has studied the flora of the little islands of Northe-West Sardinia. In a former note he has referred on Isola Piana, in this one he refers on: Isola Rossa, Isola dei Porri, and Isola Foradada.

After having done the census of the species, notifying particularly the dominant ones and after having put in evidence the principal plant communities he kept his attention on some endemic species two of which are probable endemisms new to the science: Olea europaea L. v. latifolia (mihi) and Smilax aspera L. v. inermis (mihi), coming to the conclusion:

1°) The study should confirm the hypothesis that in the little islands may be manteined species, or ancient in regression, or recent in variation the recessive characters of which would be substracted to overcome of the dominant charaters of a largest population;

2°) The florae of the four islands, for theier geographical position are the expression of the Mediterranean half-dry climate;

3°) They present their plant communities from which springs the autonomy of the different «Ecoidi» with theier different predominance established by the equilibrium attained in them.     

Ricerche biochimiche,biofisiche e istochimiche intorno al problema della metacromasia

Con 10 Figure in bianco-nero e 5 a colori nel TestoIl presente lavoro è stato eseguito usufruendo in parte anche di un contributo del Consiglio Nazionale delle Ricerche.     

La sostanza gomori-positiva della neuroipofisi del ratto dopo surrenectomia e trattamento con corticoidi surrenali e sale

Riassunto Gli AA. studiano l'effetto della surrenectomia e del trattamento con sale ed estratti corticali sulla sostanza Gomori-positiva della neuroipofisi del ratto. La surrenectomia determina una spiccata diminuzione della sostanza ehe non è in rapporto a fenomeni aspecifici dell'intervento operatorio in quanto non si osserva nell'animale sottoposto a finta surrenectomia. La somministrazione isolata di sale o di sostanze corticali la eleva quantitativamente senza riportarla alla norma: quantità pressochè normali si riscontrano solo con trattamento associato di sostanze corticali e sale. I risultati della ricerca confermano 1'esistenza di correlazioni tra sostanza di Gomori neuroipofisaria e corteccia surrenale.     

Dinamica della vegetazione forestale su tempi plurimillenari: problemi e prospettive

Abstract

The pollen records, combining long duration with high resolution and so providing information on different types of processes occurring on different time-scales, stress the importance of the temporal dimension in the study of biological processes. The history of the vegetation of the last tens of thousands of years indicates that the presentday widespread diffusion of forests at the middle latitudes is exceptional rather than normal. An example of processes seemingly similar, but with presumably different causes, is shown: the exponential growth of past plant populations, ascribed in some cases to the reproductive potential of the species concerned, and in other cases to changes of climatic and/or environmental conditions.     

La vegetazione delle isole Palmaria e Tino (Golfo della Spezia)

Abstract

The vegetation of the Palmaria and Tino Islands (Gulf of La Spezia). — The vegetation of the Palmaria and Tino islands in the Gulf of La Spezia shows various aspects although they are completely calcareous and do not exceed two hundred meters in height. Along the coast, we have noticed some small beaches with a few psammophytes, and some cliffs vertically overlooking the sea with the endemic Centaurea cineraria var. veneris and with a few shrubs (among which I would like to mention Pinus halepensis) that become bigger and bigger and grow in number with the altitude. On the southern side of Palmaria the Mediterranean « maquis » with Calicotome spinosa, Cistus monspeliensis, Myrtus communis and Pistacia lentiscus is to be noticed. This bush is either compact or rarefied so that it makes a sort of « garigue » on limestone with Euphorbia dendroides, Helichrysum stoechas, Ruta chalepensis, Thymus vulgaris. Owing to the fact that some land strips of Palmaria escaped from fire a thermophilous vegetation is to be found, with a few trees of Pinus halepensis and with a thick undergrowth of Euphorbia dendroides, Cistus incanus, Pistacia lentiscus, Myrtus communis, Smilax aspera. The vegetation of the northern side of Palmaria and Tino is less thermophilous, together with a thick wood of Quercus ilex with some plants of Quercus pubescens and with undergrowth of Viburnum tinus, Smilax aspera, Smilax mauritanica, Coronilla emerus; this wood, especially in the higher part of Palmaria, shows some glades where Erica arborea, Cistus salvifolius, Dorycnium hirsutum grow, with some entities which are distributed quite far from the sea, such as Peucedanum cervaria. Still on the northern side of Palmaria there are some traces of chestnut woods with Castanea sativa, Quercus pubescens, Ostrya carpinifolia, Corylus avellana, Cytisus laburnum and with some plants that usually grow in the cooler areas among the chestnut woods and often in the beech woods like Daphne laureola, Digitalis lutea, Helleborus foetidus and Sesleria autumnalis. A comparison between the biological spectrum of the two islands with the one of Capo Caccia in north western Sardinia and of Marettimo island in western Sicily, clearly shows that in going down southwards, a strong increase of the therophytes (respectively 29,57%, 41,73%, 49,59%), of the chamaephytes and of the nanophanerophytes (13,53%, 16,94%, 18,47%) is to be noticed, while the hemicryptophytes decrease (35,33%, 22,72%, 21,28%). Besides, the vegetation of Capo Caccia although being situated half way between the two Ligurian islands and Marettimo, is much more similar to the latter one; evidently Palmaria and Tino are conditioned by their closeness to the La Spezia coasts while having a climate quite different from them.