摘要:

Of the four common Australasian cymatiids studied,Cabestana spengleriandMayena australasiafeed almost entirely on simple ascidians.Monoplex australasiaefeeds on bivalves as well as on ascidians andCharonia rubicundafeeds on a variety of echinoderms. All species locate their prey by chemoreception of current born prey substances.Charonia rubicundais a nocturnal predator while the other species feed almost continually.

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00748.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The dascilloid beetles formerly included the families Clambidae, Eucinetidae, Helotidae and Dascillidae. The superfamily Dascilloidea is now re‐defined to include only the Dascillidae, to which are added the families Rhipiceridae and Karumiidae. The relations of the new superfamily are discusse

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00749.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The postembryonic development of the three colour varieties ofEnoplognatha ovata(CI.) was studied in the field and in the laboratory for two generations. Native and European spiders of this species were compared. Estimates of the number and duration of each stage were obtained from laboratory mating studies and verified by field studies. Males and females matured after five instars. Males matured faster than females but did not live as long. Each instar was characterized by several measurable parameters. All varieties over‐winter in the second instar. Sexes could be easily separated at the fourth instar by comparing the ratio of the tarsal to patellar width of the pedipalps. Sexual dimorphism occurs at maturation ecdysis. Filial and mating studies indicate that the three colour varieties belong to a single specie

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00750.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Four galaxiid species in two genera are recognized and redescribed from the South American region, viz.,Galaxias maculatus(Jenyns),G. plateiSteindachner,G. globicepsEigenmann, andBrachygalaxias bullocki(Regan). All of these species occur in Chile, butG. maculatusandG. plateioccur also east of the Andean divide in Argentina, in Tierra del Fuego, and the Falkland Islands. The two species east of the Andes are regarded as having crossed the mountains from west to east. The galaxiids, together withAplochiton(family Aplochitonidae) andGeotria(family Petromyzonidae), are regarded as southern circumpolar elements in the South American freshwater fish fauna, distinct from the group of species of Amazonian derivation (trichomycterids,Nematogenys, Diplomystes, Cheirodon, etc.) and distinct also from oceanic derivatives, either recent (atherinids) or ancient (serranids).

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00751.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The gross anatomy and internal architecture of the jaw musculature inRattus norvegicushas been studied using a combination of gross dissection, thick sectioning and histological techniques. As the basis of an examination of the mechanics of the muscles, the following are described:temporal, masseter, internal and external pterygoids, digastric, mylohyoid, geniohyoid and transverse mandibular.On the basis of their anatomy, it is concluded that these muscles form a series of slings around the jaw:a vertical sling (anterior temporal and deep masseter in particular) suspending the jaw from the cranium; a horizontal sling (posterior temporal and superficial masseter) initiating and controlling horizontal movements. The pterygoids and the suprazygomatic slip of the posterior temporal probably form a subsidiary sling and act to stabilize the jaw and particularly the condyle during movement.

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00752.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

‘Tonic’ and ‘phasic’ muscle fibre types can be distinguished histologically, using either histochemical techniques or by staining for lipid with Sudan black B. As muscles of mastication not only move the lower jaw of the rat, a ‘phasic’ action, but also suspend it from the cranium, a ‘tonic’ activity, some indication of the contribution of the major muscles to these functions has been gained from an examination of the fibre content of transverse frozen sections stained with Sudan black B. The numbers of ‘pale’ (‘phasic’) and ‘dark’ (‘tonic’) fibres were counted using a montage at a magnification of 60. Results suggest that the anterior temporal, deep masseter and external pterygoid have an important tonic action in stabilizing the position of the lower jaw as well as contributing to the production of movement; and that the superficial masseter and posterior temporal, in particular, have an almost completely phasic action. These conclusions are entirely consistent with the probable functions of the musc

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00753.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

A mechanical model of the muscles of mastication and their effect in producing movement of the lower jaw in the rat has been constructed using the concept of the ‘central fibre’. The relative forces these muscles can exert along their lines of action have been calculated. The vectors of the force in the horizontal, vertical and transverse planes have been found. Using these data, the distribution of vector forces about the jaw in the rest position has been demonstrated. The moments of the muscles about the joint in the rest position and in positions corresponding to those taken by the mandible at the beginning of each stroke during the cycles of ingestion and mastication have been calculated. The changes in the moment of each muscle produced by changes in the position of the jaw have been assessed and the effective action of each described.All the muscles tend to elevate the mandible and, with the exception of the anterior and poterior temporal, to protract it. The posterior temporal is the main retractor of the jaw but may be assisted by the anterior temporal. In addition to stabilizing the vertical and horizontal positions of the jaw in the rest position and during free movements, the deep masseter and anterior temporal elevate the lower jaw during the power stroke of mastication. The anterior deep masseter and its infra‐orbital part have the same function during the incisive stroke of ingestion and are probably assisted by the deep masseter. In addition to protracting the mandible, the superficial masseter may act as a regulator of jaw position during the power stroke of mastication and in the incisive stroke of ingestion. The internal and external pterygoids are considered to have a predominantly stabilizing function.Calculation of the forces acting about the molars during the power stroke of mastication indicates that the jaw is in equilibrium in this position and there is no load on the joint. However during the incisive stroke of ingestion the joint is functioning as a lever of the third order and is heavily l

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00754.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Metrical characteristics of Mueller's rats of precisely known age have not previously been available. Observations on the growth and sexual maturation of laboratory‐reared individuals have been made and regressions calculated for the more useful characters. The equations so obtained are applied to published data of other worker

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00755.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0024-4082    

DOI:10.1111/j.1096-3642.1971.tb00748a.x

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY