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Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The mathematical expression of biological temperature functions on the basis of Van't Hoffs rule is unsatisfactory. This fact led Krogh (1914) to present a standard curve, which was meant to demonstrate the basic uniformity of temperature relationships of numerous biological processes. This standard curve has served as a reference point in many papers up to the present time. Simple comparison of curve shapes is difficult for carious reasons and does not allow exact statements. Krogh himself has not attempted to define the shape of his standard curve mathematically. A pertinent proposal by Jørgensen (1916) remained unnoticed by most biologists, although it was suitable mathematically. Last year I have proposed a modification of the Arrhenius formula for expressing biological processes mathematically, in which, instead of the absolute zero (−273° C), a smaller value appeared as biological zero temperature: where Y=speed of the process at temperature t; m=maximum speed of the process at t=; z=biological zero; n=a very great number. The three parameters can be calculated from observed data. Only the determination of z is somewhat more difficult. The application of the new formula to several examples from literature led to very good results. In the present paper it is applied to the observed values on which Krogh based his standard curve. This procedure demonstrates that the new formula represents the values in many cases with a high degree of exactness. In addition, the new curve allows the representation of the numbers given by Krogh on the relation between temperature and respiration in Tenebrio-pupae, which could not be brought into coincidence with the standard curve. A number of further examples have thus demonstrated that the new formula is suited for an exact representation of biological temperature functions. Single numbers - like the Q or μ values - cannot express biological temperature functions. The three parameters contained in the new formulare are the minimum requirements for a quantitative reproduction of a curve pattern. The new formula has also been applied to express the relation between temperature and the speed of development of Aedes taeniorhynchus. In this case too it proves to be superior to the method of Jørgensen. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a brief description of the most common method of sampling foraminiferans from recent sediments and of the foraminiferan fauna of the North Sea. Distribution charts of foraminiferans in the North Sea demonstrate the influence of the Atlantic Ocean water with a slightly higher salinity in the northern part. With the exception of some very rare forms, the recent North Sea Foraminifera are illustrated and their genera briefly characterized. One new species, Trifarina pygmaea spec. nov., is described. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The medusa Eutonina indicans ( Romanes 1876) represents a circumpolar northern boreal species. In the European seas it has its southern limits of distribution in the southern North Sea, where it is common during late spring and early summer. The present paper is concerned with the formerly unknown polyp generation. It was possible to rear polyps from fertilized medusa eggs to full size; they formed colonies and produced gonangia and young medusae. Thus, morphology and development of the single polyp, colony, and young medusa could be described in detail. The systematic position of Eutonina indicans is discussed briefly, and a diagnosis of the species, including the two generations, given. [ABSTRACT FROM AUTHOR]

The paper deals with the structure of the olfactory organ, its accessory parts and the forebrain in the deep-sea fish Aphanopus carbo. On each side of the head only one opening leads to the olfactory chamber. The olfactory folds are arranged in a rosette-like pattern, resembling the 360°-type. Secondary folds on the main folds may serve as an enlargement of the surface of the olfactory epithelium. Most of the surface area of the olfactory folds is covered by the olfactory epithelium, indicating that the receptive area is of optimal extension. The histological structure of the olfactory epithelium is similar to that in other teleost species. The number of olfactory receptors amounts to about 5×10 to 10 for the single organ. Numerous secretory cells of unknown function are located within the olfactory epithelium. The olfactory chamber is enlarged by three accessory sacs: Two ethmoidal sacs and one lacrymal sac (consisting of two parts). These sacs serve as ventilation aparatus which causes a permanent water current within the olfactory chamber and between the olfactory folds. The action of the accessory sacs is induced by the splanchnokinetic. The forebrain of Aphanopus carbo is well developed; its size ranges between that of forebrains in microsmatic and macrosmatic teleost species. A detailed investigation of the forebrain is in preparation. The diagnosis of the different parts of the olfactory apparatus of Aphanopus carbo demonstrates clearly that - in addition to the eye - this sense organ is well developed (relative to that in other teleosts). This fact suggests that Aphanopus carbo is related to a group of teleost species characterized by optical and olfactory orientation mechanisms of high performance. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polyps and medusae differ in regard to habitats, evolution, and morphological structures. In order to replace the former taxonomic systems which deal with polyp and medusa generations separately, by a single valid classification including both generations, knowledge of all essential life history phases is necessary. Modern methods of culturing marine hydroids are outlined briefly. Successful culturing provides the means to link formerly unidentified polyps or medusae with one another. The present paper is concerned with the hydroid Eucheilota maculata Hartlaub, the medusa of which is common in the southern North Sea. The polyps formerly unknown have been reared from fertilized eggs of the medusae. They were raised to full size, formed colonies, and produced gonangia and medusae. Thus the morphology of the single polyp, the polyp colony, and of the young medusa could be investigated in detail. The nematocyst equipment of the two generations and of all developmental stages is described as well as the number of chromosomes. The systematic position of the genus Eucheilota is discussed and the diagnosis of the species E. maculata, including the two generations, given. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Growth and development are basic features in the life of organisms; culturing in the laboratory is the method for the elucidation of these processes. Their analysis leads to an understanding of morphological and taxonomical interrelationships and is the basis for work on developmental physiology. In previous investigations growth and development have been studied in Urospora, Acrosiphonia and Spongomorpha ( Kornmann 1965, 1966, 1967). In the present paper, the intercalary growth of a Chaetomorpha species was analysed. Under the conditions of the experiment, a sporeling elongated into a filament of 60 cm within 74 days. Length was doubled in a period of 4 days, according to the simple exponential function y=a. The value of the base a depends on cultural conditions. In this rapidly growing object, spiral growth, already demonstrated in Chaetomorpha melagonium and Cladophora by Frei & Preston (1961b) was evident, a complete rotation at the top of a 25 cm-filament needing only 15 minutes. Rotation speed increases from the base to the top of a filament and varies in a daily rhythm. Many cells of the filament are not equal in height, the lower of a pair of sister-cells being generally shorter. Consequently, the interval between subsequent cell divisions varies from 3 to 5 days. Cell division is not synchronized with the division of the numerous nuclei. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Metabolic rate does not strictly follow changes of influencing parameters. O-consumption by fish is ordinarily said to be independent from O-pressure throughout a wide range. This constancy is probably the result of a regulation. The metabolic rate itself or an auxiliary mechanism 'before' or 'after' metabolism may be regulated. On the basis of van Dam's paper (1938) and our own experiments, the problem whether or not O-pressure in blood serves as a regulated auxiliary mechanism in order to maintain a certain metabolic constancy is discussed. The disadvantage of such a regulation would be the energy demand of increased ventilation and circulation as compensating mechanisms. In accordance with this assumption we have found a rise in O-consumption at a somewhat reduced O-pressure. Locomotory behaviour supports the constancy of metabolic rate; thus a contrary shift of the temperature preferendum after application of substances which influence metabolism has been found. [ABSTRACT FROM AUTHOR]

Both tremorine and arecoline cause a drop in body temperature in small laboratory animals (mice, rats, guinea pigs) as well as tremor, rigor and peripheric effects. The purpose of this paper is (1) to characterize the up-until-now unknown hypothermic effect of arecoline, as compared with tremorine, and (2) to check the action of drugs used in Parkinson's disease and others on this hypothermia in mice in order to obtain information on the action of tremorine and arecoline on thermoregulation and on their antagonists. The relations between dose and body temperature of male mice kept at different ambient temperatures after intraperitoneal injection of arecoline or tremorine and the influences of antagonists (in view of tremor) on hypothermia have been studied. The hypothermic action following the use of tremorine is more continuous and more pronounced than that following arecoline. Judged by the same degree of body temperature depression, the effect of tremorine is five to 10 times stronger than that of arecoline. Scopolamine, atropine, benactycine and trihexyphenidyl block the hypothermic effect of tremorine and arecoline; hypothermia after arecoline is not influenced by caramiphen; antiparkin, butylscopolamine, as well as the phenothiazine-derivatives ethopropazine, promethazine and diethazine, are also ineffective; methylatropine reduces the arecoline-hypothermia only in high doses. Hypothermia after arecoline and tremorine is mainly based on a central action. The effects of several central cholinolytics and the antihypothermic inefficiency of phenothiazines, used in Parkinson's disease and against motoric effects of tremorine and arecoline, demonstrate a difference within this group of drugs. The trigger in hypothermic action is a cholinergic one. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to stimulate scientific contacts between the few German microbiologists devoted to studying the ecology of aquatic microorganisms, and to work out agreements on methodical problems, a meeting was held at the marine station of the Biologische Anstalt Helgoland from June 24 to 26, 1964. The main topic discussed was: 'The methods used in aquatic microbiology'. The present report contains summaries of the papers presented, some of the discussions and a brief description of different microbiological methods demonstrated by the participants (different types of samplers, sampling from board of the research vessel 'Uthörn', culture media, counting techniques and determination of bacterial activity). The second meeting on the same subject will be held in Plön, West Germany, in 1965. [ABSTRACT FROM AUTHOR]

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Helgoland Marine Research is the property of BioMed Central and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)