摘要:

AbstractBjerring, H. C. (Section of Palaeozoology, Swedish Museum of Natural History, Stockholm, Sweden.)The rhinal bone and its evolutionary significance. Zool. Scripta 1 (5): 193–201, 1972.– On the basis of serially sectioned embryos ofAmia calva, the ethmoidal region of the endocranium and certain adjacent exo‐skeletal elements are analysed. The results include evidence of the existence of branchial moieties pertaining to the first or premandibular metamere. Each of these moieties comprises infrapharyngobranchial (the ethmobasal), suprapharyngobranchial (the orbitonasal lamina), and epibranchial (the palatoquadrate pterygoid process) endoskeletal components as well as horizontal infrapharyngeal (the vomer), ascending infrapharyngeal (the rhinal), and epal (the dermopalatines and ectopterygoid) dental plates. The anterior cerebral arteries may represent the efferent blood vessels of the first‐metamere branchial moieties. A hypothesis on the origin of the nasal sacs is

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1972.tb00577.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractEkman, J. (Osteological Research Laboratory. University of Stockholm, Solna, Sweden.) Theurus female(Bos primigeniusBoj.) from Slâgurp, Southern Sweden.Zool. Scripta 1 (5): 203–205, 1972.– On the basis of measurements of an almost complete female urus skeleton from Slågarp, Scania, a discussion is given of the size and postglacial microevolution of the genus Bos within the Nordic area. This specimen from early postglacial time (first half of the Boreal period) turned out to be the smallest urus female hitherto known within this area. The teeth, however, are large. In a recent paper Degerbøl assumes that the urus had reached its lowest body‐size already during early postglacial times, and then remained constant, while the teeth gradually decreased in size. The results of the present investigation corroborate this theory. One explanation might be that the decrease in size of the teeth lagged behind that undergone by the body during late glaci

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1972.tb00578.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractÅkesson, B. (Department of Zoology, University of Gothenburg, Göteborg, Sweden.)Incipient reproductive isolation between geographic populations ofOphryotrocha labronica (Polychaeta, Dorvilleidae). Zocl. Scripta 1 (5): 207–210, 1972.–The mechanism of sex determination and the incipient reproductive isolation between geographic populations ofOphryotrocha labronicaare studied in intra‐ and interpopulation crosses. Two populations from the Naples area and one from Leghorn are employed in the crosses. The considerable genetic difference between the Leghorn population and any of the Naples populations is reflected in some crossing combinations by changes in sex ratios, by occurrence of individuals with a reduced viability in the progeny, by a decreased mating propensity, and by discrimination of mates from alien populations. It is stated that the changes in sex ratios, the decreased mating propensity, the dwarfed individuals in the progeny, and the preferential mating all reflect the incompatibility of gene complexes. The differences between reciprocal crosses are not fully explained. The occurrence of extranuclear DNA, as well as the existence of a maternal heredity in intrapopulation crosses, indicate that cytoplasmic inheritance may be one of the factors behind these reciprocal diff

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1972.tb00579.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractBerg, G. (Department of Zoology, University of Gothenburg, Göteborg, Sweden.)Studies onNipponnemertesFriedrich, 1968 (Nemertini, Hoplonemertini). I. Redescription of Nipponnemertes pulcher(Johnston, 1837) with special reference to intraspecific variation of the taxonomical characters.Zool. Scripta 1 (5): 211–225, 1972.—Nipponnemertes pulcheris redescribed on the basis of a large number of specimens, and the use of shape and structure of the different organ systems as taxonomic criteria for the species is tested. On the basis of this description the species is transferred to the genusNipponnemertesFriedrich,

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1972.tb00580.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractMalmberg, G. {Department of Zoology, University of Stockholm, Stockholm, Sweden.)On the early development of the protonephridial systems in some species belonging to the generaDiphyllobothrium, Triaenophorus and Schistocephalus{Cestoda, Pseudophyllidea).Zool. Scripta 1 (5): 227–228, 1972.–The protonephridial systems of coracidia (oncospheres) and procercoids of fourDiphyllobothriumspecies, ofTriaenophorus nodulosus(Pallas) and ofSchistocephalus solidus(Muller) were studied. In the oncospheres ofDiphyllobothriumandSchistocephalusthe two flame bulbs of the primary protonephridial system were present, but not in the oncospheres ofTriaenophorus.InSchistocephalusthe two flame bulbs were found to be inactive in the oncosphere (studied inside the coracidium), but very active in the youngest procercoids, which may imply that the primary protonephridial system does not start its function until the oncosphere has entered the copepod body cavity. The primary protonephridial system of theTriaenophorusprocercoids was totally (most specimens) or partly reduced. The secondary protonephridial system, however, began developing more or less simultaneously with the integumental hooklets, the cercomer and the first calcareous bodies, which is in accordance with what is described concerningDiphyllobothrium.The ciliated, excretory bladder described by Rosen in 1919 was found to be a posteriorly open invagination, surrounding the “cercomer shaft”. Reverse bends of the posterior main canals of the secondary system are located closely around the wall of, though very likely not emptying into this invag

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1972.tb00581.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY

摘要:

AbstractKiefer, F. (Staatliches Institut fur Seenforschung und Seenbewirtschaftung, Abteilung Max‐Auerbach‐Institut, Kcnstanz Bodensee, GFR)Zur Kenntnis von Morphologie und Systematik einiger Arten der GattungDiaptomus(s. restr.) (Crustacea, Copepoda).Zool. Scripta 1 (5): 229–240, 1972.–Based on a detailed morphological comparison of the type material ofDiaptomus mirusLilljeb. and of some Diaptomus‐populations from SE Europe and Anatolia, the author has distinguished 3 species of this group:Diaptomus mirusLilljeb., occurring in western Sibiria and perhaps in the central region of the European USSR;D. falsomirussp. n. in Bulgaria and in Anatolia;D. serbicusGjorg. being found in Italy, in Yugoslavia, in the island of Corfu (Greece), in Bulgaria, in Rumania and perhaps in Ukraina. In addition, a more exact description is given ofDiaptomus glacialisLilljeb. based on the type material.–In an appendixDiaptomus kostromanussp. n. is described on material from the European USSR.ZusammenfassungEine eingehende vergleichend‐morphologische Untersuchung des ori‐ginalen Materiales vonDiaptomus mirusLilljeb. und mshrererDiap‐fom‐5‐Populationen aus Siidosteuropa und Anatolien führt zum Ergebnis, daß drei verschiedene Arten dieser Gruppe zu unterschei‐den sind:Diaptomus mirusLilljeb. mit Vorkommen in W. Sibirien und vielleicht im mittleren Teil der europäischen USSR;D. falsomirussp. n. in Bulgarien und Anatolien;D. serbicusGjorg., ge‐funden in Italien, Jugoslawien, Bulgarien, Rumänien, auf der lnsel Korfu (Griechenland) und vielleicht in der Ukraine. Zusätzlich wirdDiaptomus glacialisLilljeb. ausführlicher gekennzeichnet. –Diaptomus kostromanussp. n. wird in einem Nachtrag beschrieben (Ma

ISSN:0300-3256    

DOI:10.1111/j.1463-6409.1972.tb00582.x

出版商:Blackwell Publishing Ltd    

年代:1972

数据来源: WILEY