Untersuchungen der Pollenkörner vonAlnus rugosa (Du Roi) Spreng. im Interferenzmikroskop nach Nomarski

Summary With the aid of the differential interference contrast microscope (systemNomarski), the pollen grains ofAlnus rugosa were examined. The characteristic surface structure, the arci and certain structures in the vestibules of the pores are thus very clearly visible. A further use of this microscopic method may be possible for the investigation of pollen grains.     

Nachweis circanualer Periodik bei der Quappe (Lota lota L.) (Pisces,Gadidae)

Summary Investigations on daily rhythm in the burbot (Lota lota L.) in the Arctic Circle showed that a phase-shift in the locomotor activity occurred under nLD; the fish, which is night-active in the summer, phase-shifted 180 degrees in relation to the phase-timing factor. This phase-shift was also found in a fish kept in artificial light (LD 1212) which occurred at almost the same time of year. Accordingly an endogenous circaannual rhythm is suggested.

---

---

Die Untersuchungen erfolgten mit Unterstützung der Max-Planck-Gesellschaft zur Förderung der Wissenschaften und des Staatlichen Schwedischen Naturwissenschaftlichen Forschungsrates.     

Zur funktionellen Bedeutung der räumlichen Anordnung des Kristallkegels zum Rhabdom im Auge der Trachtbiene (Apis mellifica L.)

Summary The granular material found in the 4 sectors of the crystalline cone of varying electron density possibly causes a different absorption of incident polarized light. As the quadrants of the crystalline cone are rotated against the quadrants of the rhabdom, we can conclude that each rhabdomere may be stimulated by light of different physical qualities consequently providing a 4-to 8-fold pattern in the rhabdom of the ommatidia.

---

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Eine bisher unbekannte endokrine Drüse im Kopf vonScutigera coleoptrata L. (Chilopoda,Notostigmophora)

Summary A hitherto unknown endocrine gland in the head ofScutigera coleoptrata is described. It is attached to a small blood vessel. Its cells are typical podocytes. Between the pedicells and along the lateral cell membranes, there are many intercellulary spaces. The fine structure of the gland is very similar to that of the collar gland in the diplopodPolyxenus lagurus.     

Untersuchungen zur Verdauungsphysiologie vonFormica polyctena Foerst. (Hymenoptera,Formicidae)

Summary In this investigation the spectrum of digestive-acting carbohydrates present inFormica polyctena Foerst. was analysed. The digestive tract of worker ants was dissected and the enzymatic activity tested by incubation with different carbohydrates. The results for crop, midgut, malpighian tubes and hindgut are given in the Table.     

Halbe haploide Chromosomenzahl im Hoden vonMyrmica sulcinodis Nyl. (Formicidae)

Summary In the testes ofMyrmica sulcinodis there are not only haploid and some diploid cells to be found, as in the testes ofM. ruginodis, M. sabulsti andM. rubida, but a large mass of cells that have only half the haploid chromosome number. The diploid chromosome number ofM. sulcinodis is 56, those of six otherMyrmica species are between 42 and 48.     

Amphibious vision inCoryphoblennius galerita L. (Perciformes)

The morphology of the ophthalmic cornea in the blenniid fishCoryphoblennius galerita (Teleostei) shows adaptation to the amphibious life. Amphibious vision is provided by a flattened area within the cornea. Eyes of other, non-amphibious blenniids are compared with those ofC. galerita.     

A queen bee extract (Apis mellifera L.) (Hymenoptera) reduces the fecundity ofTenebrio molitor L. (Coleoptera)

Summary 3 different doses of crude queen bee extract were administered to pairs of adultTenebrio molitor L.; the extract exerted an inhibitory action on fecundity, but did not induce complete sterility of the females.     

Experimentelle Untersuchungen zum Wirkungsmechanismus der beiden entwicklungsphysiologisch aktiven Fraktionen des «Gehirnhormons» der Insekten (Aktivationsfaktor I und II) auf die Prothoracaldrüse

Summary 2 prothoracotropical factors (activation factor I and II) have been obtained by gel filtration techniques from brains and corpora cardiaca of the cockroachPeriplaneta americana. In contrast to activation factor II, activation factor I caused significant influence of RNA synthesis. The RNA pattern of prothoracic glands stimulated by activation factor I as demonstrated by polyacrylamide gel electrophoresis consists of different kinds of RNA. Short time incubation revealed effects on sRNA synthesis, while long time incubation demonstrated predominantly increase of ribosomal RNA synthesis. Measurements of the membrane potential of the prothoracic gland cells of the wax mothGalleria mellonella indicated an increase by activation factor II; activation factor I was without any visible effect. Our results demonstrate for the first time that the two activation factors induce different effects at cellular level.

---

---

Für technische Unterstützung danken wir FräuleinA. Zinsser und FrauR. Meissner.

---

Durchgeführt mit Mitteln des Ministeriums für Wissenschaft und Technik und mit Unterstützung durch die Sächsische Akademie der Wissenschaften zu Leipzig.     

Heterochromosomen beiVipera berus L. (Viperidae,Serpentes)

Summary A dimorphic pair of chromosomes was found among the macrochromosomes in mitosis of females ofVipera berus L. It corresponds to a pair of medium-sized chromosomes in the male. The conclusion is drawn that females are heterogametic (ZW-type), males being homogametic (ZZ-type). Similar observations were made inVipera aspis L.,Natrix natrix L., andNatrix maura L.     

La formule chromosomique deSorex minutus L. (Mammalia-Insectivora)

Summary The chromosome complement ofSorex minutus L. has been determined. The caryotype is characterized by a diploid number of 42 and by aNF (fundamental number) of 56. The sex-chromosomes are of theX−Y type usual in mammals. The origin and the evolution of the chromosome set ofS. minutus, S. unguiculatus, andS. araneus have been discussed.      

Chromosome change during growth inPuschkinia libanotica L. (Liliaceae)

Summary The variation in chromosome size in root-tip meristem ofPuschkinia libanotica L. was studied at different days of root growth with special attention to DNA, RNA, total protein and histone contents. The results show that the size and organisation of chromosomes even within the one tissue is subject to considerable change during growth and development.The author is thankful to Prof. H. Rees, FRS, Department of Agricultural Botany, University College of Wales, Aberystwyth, Wales, U.K., for his guidance and to University College of Wales, Aberystwyth, for granting him a SRC fellowship.     

X-ray microanalysis in pearls ofMytilus edulis L. (bivalvia)

Summary Metacercariae feeding on the tissues of Mytilus edulis deposit their excretes into the mussel. The clusters of excretes are surrounded by a pearl sac. Increasing amounts of Ca-proteids are transported into the pearl sac epithelium and into the pearl.     

Effects of reserpine on development of Oedipoda coerulescens L. (Acrididae, Orthoptera) (author's transl)

Inhibitory effects of reserpine on ecdysis and chromatic adaptation in Oedipoda appear to be linked with changes observed in both neural and neuro-endocrine regulating systems.     

Free amino acids of the hemolymph ofAnacridum aegyptium L. (orthoptera)

Riassunto Sono stati determinati 14 aminoacidi liberi nell'emolinfa: di cssi acido glutamico, glicina e prolina rappresentano insieme il 50% e più del contenuto totale. Le ninfe verdi contengono meno glicina e acido aspartico e più treonina e fenilalanina in confronto alle ninfe brune. Gli individui adulti mostrano in contenuto relativo di aminoacidi diverso dalle ninfe e fra i due sessi. Somministrazione di triptofano a ninfe brune non ha dato variazioni negli aminoacidi liberi, non aumento dell'aminoacido stesso, né presenza di prodotti del suo metabolismo nel sangue.     

Intersubspecific sex chromosome difference inCitellus citellus L. (Rodentia,Sciuridae)

Summary The autosomal karyotypes of all subspecies studied ofCitellus citellus from Bulgaria do not differ. The X chromosome, by contrast, is different in 1 of the subspecies where it seems to have undergone a pericentric inversion.The authors wish to express their sincere thanks to Prof. Ts. Peshev (Sofia University, Department of Zoology) for providing and identifying the subspecies and also to D. Todorova for her skilful technical help.     

Die Probeentnahme in kinetischen Stoffwechseluntersuchungen mit WasserlinsenLemna minor L. (Lemnaceen)

Summary A suitable sample technique for duckweed (Lemnaceae) in kinetic studies of photosynthesis or other metabolic processes is described. It enables one to remove plants from a culture chamber in a closed gas and/or nutrient solution circuit without disturbing the system.     

The innervation of the prothoracic glands ofCerura vinula L. (Lepidoptera)

Zusammenfassung Die Prothoraxdrüsen vonCerura vinula L. werden von Nerven innerviert, deren Axone neurosekretorische Grana enthalten und ausserdem in synaptischer Verbindung mit den Drüsenzellen stehen. Diese beiden Tatsachen sprechen für einedirekte Aktivierung der Prothoraxdrüsen durch Neurohormone.

---

---

This investigation was supported by Deutsche Forschungsgemeinschaft.

---

To the 60th birthday of Prof. Dr. G.Birukow.     

Occurrence of monocentric chromosomes inPieris brassicae L. (Lepidoptera,Pieridae)

Summary Monocentric chromosomes with localized kinetochores were obtained inPieris brassicae (Lepidoptera, Pieridae) by using colchicine treatment and air-drying method.We wish to express our thanks to Dr A.K. Datta-Gupta, Professor and Head of our Department for providing the research facilities and for encouragement.