The Reproduction of the Entozoic Nemertean Gononemertes australiensis Gibson (Nemertea: Hoplonemertea : Monostylifera) - Gonads, Gametes, Embryonic Development and Larval Development

1979 ◽  
Vol 30 (5) ◽  
pp. 661 ◽  
Author(s):  
EA Egan ◽  
DT Anderson
Keyword(s):  
Embryonic Development ◽  
Larval Development ◽  
New South ◽  
Mature Female ◽  
The Body ◽  
Water Current ◽  
Young Larva ◽  
South Wales ◽  
Larval Structure ◽  
Host Invasion

G. australiensis is an entozoic nemertean found in the atrium of the ascidian Pyura pachydermatina (Herdman) var. intermedia Herdman. The host is common in the low intertidal and shallow sublittoral waters of the Sydney region of New South Wales. The nemertean is dioecious and possesses numerous gonads. In mature female worms, oocytes at different stages of maturity are always found throughout the body. The more mature oocytes lie close to the gut. Each temporary gonad produces several oocytes. The mature male worms contain ripe testes close packed within the parenchymal tissue along the body. The spermatozoon of G. australiensis has a head 6.5 µm long and a tail 38 µm in length. The head is rod- shaped with a blunt simple acrosome. The base of the head is surrounded by a mitochondria1 bulge which also encloses the connecting piece. A close apposition between the nucleus and the mitochondrion occurs in this area. The sperm is intermediate in type between primitive and modified nemertean spermatozoa. The egg of G. australiensis is spherical, yolky, 0.18mm in diameter and surrounded by a glutinous membrane. Fertilization is external. Cleavage, gastrulation and later embryonic development are similar to those of other hoplonemerteans and the resulting larva is of the hoplonemertean type. The larva is free- swimming for 3-5 days before invading a host. Some features of larval structure and behaviour are specializations associated with the entozoic habit of the nemertean. The development of the larval ocelli, lost soon after host invasion, is one of these. The young larva is photopositive, but after the ocelli have formed it becomes photonegative. Older larvae respond to a water current by an attachment response. No stomodaeum is formed during embryonic or larval development and completion of the differentiation of the proboscis is delayed until host invasion takes place. The larva exists on yolk until this time. The resources of the larva are concentrated on host location rather than on the feeding, growth and continued development typical of the larvae of other free-living hoplonemerteans.

The association between face cover and the productivity of Merino ewes in twelve NSW flocks

1967 ◽  
Vol 7 (28) ◽  
pp. 412
Author(s):  
JP Drinan ◽  
RB Dun
Keyword(s):  
Reproductive Performance ◽  
New South ◽  
New South Wales ◽  
Negative Association ◽  
The Body ◽  
Positive Correlation ◽  
South Wales ◽  
Body Weights ◽  
The Face ◽  
Fleece Weight

The association between the face cover and productivity of more than 3000 Merino ewes has been examined in 12 flocks located in the major sheep producing areas of New South Wales. Each flock was divided into Open (scores 1 and 2), Moderate (scores 3 and 4), and Muffled (scores 5 and 6) groups. A significant negative association between face cover and reproductive performance was apparent in two flocks that contained appreciable numbers of muffled-faced ewes. A similar trend was apparent in another Muffled flock, but in one other Muffled flock and four Open flocks, there was no evidence of such an association. The results from the remaining four flocks were not considered, due to the possibility that the results were confounded by face cover scoring after joining. In one Muffled flock, the body weights of weaner lambs were negatively correlated with their dams' face cover. A relationship between face cover score and total greasy fleece weight, corrected for previous reproductive performance, was absent from most flocks and negative in two, despite evidence of a positive correlation with belly weight. There was a trend to inferior fleeces of finer trade count in Moderate and Muffled groups of several flocks. Excess face cover was found to be an undesirable attribute in Merino flocks. Its importance was greatest in flocks containing appreciable numbers of muffled-faced ewes

Thermal relations of the malle fragon Amphibolurus fordi (Lacertilia : Agamidae)

1974 ◽  
Vol 22 (3) ◽  
pp. 319 ◽  
Author(s):  
HG Cogger
Keyword(s):  
Body Temperature ◽  
Field Study ◽  
New South ◽  
Close Association ◽  
The Body ◽  
Total Effect ◽  
Body Temperatures ◽  
South Wales ◽  
Wide Range ◽  
Thermal Relations

A field study of the thermal relationships of the small agamid lizard A. fordi has been carried out in two areas of mallee in central western New South Wales, where this lizard occurs only in close association with the grass Triodia scariosa. The body temperatures characteristic of various phases in this lizard's die1 cycle have been determined. The behavioural techniques employed to regulate temperature are described; they are similar to those used by a wide range of diurnal heliothermic lizards in other regions. The total effect of these thermoregulatory responses is to maintain an internal thermal environ- ment approaching homoiothermy while the lizard is active. For A. fordi the eccritic body temperature determined from animals in the field is 36.9+-0.16C. Lowering of activity thermal levels occurs in winter, and can be induced at any time by even mild starvation.

Saccocirridae (Annelida : Archiannelida) from the central coast of New South Wales

1981 ◽  
Vol 32 (3) ◽  
pp. 439 ◽  
Author(s):  
R Brown
Keyword(s):  
World Wide ◽  
New South ◽  
New South Wales ◽  
Ventral Surface ◽  
The Body ◽  
Coarse Grained ◽  
Pacific Region ◽  
Central Coast ◽  
South Wales ◽  
Turbulent Water

Saccocirrids (archiannelids) were collected from coarse-grained sediments in turbulent water from the central New South Wales coast. Saccocirrus jouinae, sp. nov., and S. tridentiger, sp, nov., are described, and S. krusadensis Alikunhi, 1948 newly recorded in Australia. In these species gonads occur only on the left side of the body and cilia are found on the ventral surface. Of the 17 species attributed to the Saccocirridae, seven species are known to have unilateral gonads and ventral ciliation. They occur only in the Indo-Pacific region. Species with gonads on both sides of the body have not been described with cilia on the ventral surface. Their distribution is world-wide.

scholarly journals Developing a beam trawl for sampling estuarine fish and crustaceans: assessment of a codend cover and effects of different sizes of mesh in the body and codend

2008 ◽  
Vol 65 (4) ◽  
pp. 687-696 ◽  
Author(s):  
Douglas Rotherham ◽  
Matt K. Broadhurst ◽  
Charles A. Gray ◽  
Daniel D. Johnson
Keyword(s):  
Experimental Approach ◽  
New South ◽  
New South Wales ◽  
Mesh Size ◽  
The Body ◽  
Estuarine Fish ◽  
Beam Trawl ◽  
South Wales ◽  
The Mean ◽  
Selection Of

Abstract Rotherham, D., Broadhurst, M. K., Gray, C. A., and Johnson, D. D. 2008. Developing a beam trawl for sampling estuarine fish and crustaceans: assessment of a codend cover and effects of different sizes of mesh in the body and codend. – ICES Journal of Marine Science, 65: 687–696. An experiment was carried out in the Clarence River (New South Wales, Australia) to test the hypotheses that fish and crustacean catches in an experimental beam trawl were affected by a codend cover and the sizes of mesh in the body and codend. The cover had no obvious effects on the catches retained in the codend. Similarly, in comparisons between trawl bodies made from 26- and 41-mm diamond-shaped mesh, there were no differences in the assemblages of fish caught, or in the mean numbers entering the codends. For one species of fish (Acanthopagrus australis), however, there were differences in the proportions caught between the trawl bodies across different size classes. There was also some evidence to suggest that mesh size in the body of the trawl influenced the size selection of school prawns (Metapenaeus macleayi). For most finfish, there were no differences in catches between codends made from 20-mm and from 29-mm mesh hung on the bar (i.e. square-shaped mesh). In contrast, mesh size in the codend was important for the size selectivity of school prawns, with smaller carapace lengths at 50% retention in the 20-mm codend. We conclude that use of a 41-mm mesh in the body and a 20-mm square mesh in the codend of the beam trawl would be appropriate for future sampling with this gear in estuaries of New South Wales. A similar experimental approach to ours is needed in adapting the beam trawl to estuaries in other parts of the world, or in developing other types of research trawl.

Variation in non-wool components of the greasy fleece over the body of Merino sheep

1984 ◽  
Vol 24 (124) ◽  
pp. 62 ◽  
Author(s):  
KJ Thornberry ◽  
KD Atkins
Keyword(s):  
Agricultural Research ◽  
New South ◽  
Correlation Coefficients ◽  
Matter Content ◽  
The Body ◽  
Research Centre ◽  
Merino Wool ◽  
South Wales ◽  
Sampling Position ◽  
One Year

Twelve one-year-old ewes were randomly selected from each of four flocks running together at pasture at the Agricultural Research Centre, Trangie, New South Wales. The flocks represented fine wool, medium wool non-Peppin and medium wool Peppin strains of Merino. Wool samples were collected from nine sites over the body of each ewe. Gradients over the fleece in percentage suint, percentage wax, wax:suint ratio, percentage dust, percentage vegetable matter and estimated clean scoured yield were demonstrated. Although flocks differed in the average level of these components, gradients were similar for the different flocks. The mid-side appeared to be a satisfactory sampling position for estimating the suint, wax, wax:suint ratio, dust and yield characteristics of the whole fleece. The mid-side values for these characteristics were similar to the average values for all nine sites and the correlation coefficients between mid-side values and the total of all sites for percentage suint, percentage wax, wax:suint ratio, percentage dust and estimated yield were 0.94, 0. 8.9, 0.90 and 0.87 respectively. These were higher than for any other single sampling position. The correlation between mid-side and the overall value for vegetable fault was only 0.56 and neither the mid-side nor any other single site appeared to be sufficiently reliable to predict total vegetable matter content.

Studies on Age, Growth, and Life History of the Pilchard, Sardinops neopilchardus (Steindachner), in Southern and Western Australia

1950 ◽  
Vol 1 (2) ◽  
pp. 221 ◽  
Author(s):  
JM Blackburn
Keyword(s):  
Growth Rate ◽  
Western Australia ◽  
New South ◽  
New South Wales ◽  
South Australia ◽  
The Body ◽  
Fish Length ◽  
Linear Type ◽  
Spawning Period ◽  
South Wales

The biology of the unexploited Australian pilchard, Sardinops neopilchardus (Steindachner), was studied from a limited material available from Victorian, Tasmanian, South Australian, and Western Australian waters. This completes the preliminary study of the species over almost the whole of its sub-continental range. In Victorian waters, the surface shoaling season is spring and summer, in South Australia, summer and autumn, and in southern Western Australia, autumn and winter; these are the spawning seasons for the respective areas. In New South Wales and Queensland waters, the shoaling season is autumn to spring, which is again a spawning period. The situation in Tasmania, where the species is rare, is probably similar to that in Victoria. On the west coast of Australia, where the species extends northward to the Tropic of Capricorn (as it also does in the east) the seasonal distribution is not clear. In all these areas pilchard occurrences are virtually limited to the bay and neritic waters. Victorian pilchards attain mean standard lengths of about 8.0, 10.5, 12.5, 14.0, and 15.5 cm. at the ages of one, two, three, four, and five years respectively. This growth rate is considerably lower than that in New South Wales. In southern Western Australia the growth rate is intermediate between the other two, but in South Australia it was not established. The average size of pilchards in the seasonal shoals appears to be greater in Western Australia than elsewhere, but no fish over 19.5 cm. standard length (9.0 in. total length) has been encountered in any of the current Australian investigations. Sexual maturity occurs earlier in Victoria than in New South Wales, sometimes at one year of age. The ring pattern of Australian pilchard scales is complex, involving yearly, spawning, and secondary rings. A hypothesis to account for the formation of spawning rings is outlined, and an earlier hypothesis relating to yearly rings is abandoned. Secondary rings occur on most scales from the same fish. In all waters the season of ring formation coincides with that of surface availability of fish, but in Victoria it is also the growing season, which makes age determination particularly difficult. The fish-length/scale-length relationship for Victorian material is of the same linear type as for New South Wales, but there are differences in the size of scales taken from the same area of the body. The possible influences of distribution, size, and condition of fish on future economic exploitation are discussed.

Population ecology of the eastern pygmy-possum (Cercartetus nanus) in a montane woodland in southern New South Wales

2014 ◽  
Vol 36 (2) ◽  
pp. 212 ◽  
Author(s):  
Jamie M. Harris ◽  
Ross L. Goldingay ◽  
Lyndon O. Brooks
Keyword(s):  
Population Dynamics ◽  
Population Ecology ◽  
New South ◽  
Local Population ◽  
New South Wales ◽  
The Body ◽  
Floral Resources ◽  
Nectar Feeding ◽  
South Wales ◽  
Cercartetus Nanus

The population dynamics of nectar-feeding non-flying mammals are poorly documented. We investigated aspects of the population ecology of the eastern pygmy-possum (Cercartetus nanus) in southern New South Wales. We captured 65 individuals over a 4-year period during 5045 trap-nights and 1179 nest-box checks. The body mass of adult males (mean ± s.e. = 24.6 ± 1.0 g) was marginally not significantly different (P = 0.08) from that of non-parous adult females (28.2 ± 1.9 g). Females gave birth to a single litter each year of 3–4 young during February–May. No juveniles were detected in spring of any year. Mark–recapture modelling suggested that survival probability was constant over time (0.78) while recapture probability (0.04–0.81) varied with season and trap effort. The local population (estimated at ~20–25 individuals) underwent a regular seasonal variation in abundance, with a decline in spring coinciding with the cessation of flowering by Banksia. A population trough in spring has been observed elsewhere. This appears to represent some local migration from the study area, suggesting a strategy of high mobility to track floral resources. Conservation of this species will depend on a more detailed understanding of how flowering drives population dynamics.

Danger Delights: Texts of Gender and Race in Aerial Performance

1996 ◽  
Vol 12 (45) ◽  
pp. 43-49
Author(s):  
Peta Tait
Keyword(s):  
New South ◽  
Judith Butler ◽  
The Body ◽  
Racial Identities ◽  
South Wales ◽  
The Social ◽  
And Gender ◽  
The 1960S ◽  
The University ◽  
Social Separation

Circus artists, especially aerial performers and wire-walkers, transgress and reconstruct the boundaries of racial and gender identity as part of their routine. In the following article, Peta Tait analyzes the careers of two twentieth-century Australian aerialists of Aboriginal descent who had to assume alternative racial identities to facilitate and enhance their careers. Both Con Colleano, who became a world-famous wire-walker in the 1920s, and Dawn de Ramirez, a side-show and circus aerialist who worked in Europe in the 1960s, undermined the social separation of masculine and feminine behaviours in their acts. Theories of the body and identity, including those of Foucault and Judith Butler, inform this critique of the performing body in circus. The author, Peta Tait, is a playwright and drama lecturer at the University of New South Wales. She is author of Original Women's Theatre (1993) and Converging Realities: Feminism in Australian Theatre (1994).

On the Identity of the Kidney Worm of Pigs in New South Wales

1924 ◽  
Vol 2 (3) ◽  
pp. 149-150 ◽  
Author(s):  
T. W. M. Cameron ◽  
I. Clunies Ross
Keyword(s):  
New South ◽  
New South Wales ◽  
The Body ◽  
Text Book ◽  
South Wales

In 1839 Diesing described Stephanurus dentatus from the kidney of the pig. His description was incorrect in two important particulars, viz.— in stating that only one spicule was present and that the vulva was in the middle of the body instead of posteriorly. These errors, although corrected by Verril in 1870 and Louise Taylor in 1899, still persist, and it was on account of this that Drabble, in 1922, basing his diagnosis on a faulty text-book description, claimed that the Kidney worm of swine in New South Wales was generally distinct from Stephanurus dentatus. This worm he called Sclerostomum renium, n. sp.

Revision of Capsaloides (Monogenea: Capsalidae) with a redescription of C. magnaspinosus Price, 1939 from the nasal tissue of Tetrapterus audax (Istiophoridae) collected off Nelson Bay, New South Wales, Australia

Zootaxa ◽  
2006 ◽  
Vol 1160 (1) ◽  
pp. 1 ◽  
Author(s):  
LESLIE A. CHISHOLM ◽  
IAN D. WHITTINGTON
Keyword(s):  
New South ◽  
New South Wales ◽  
The Body ◽  
Type Material ◽  
Careful Examination ◽  
Scanning Electron Micrographs ◽  
Locality Record ◽  
New Host ◽  
Nasal Tissue ◽  
South Wales

Capsaloides magnaspinosus (Monogenea: Capsalidae) is redescribed from whole mounts and scanning electron micrographs of material collected from the nasal tissue of the striped marlin, Tetrapterus audax (Philippe, 1887), off Nelson Bay, New South Wales, Australia. This represents a new host and locality record for this capsalid species. Capsaloides is revised based on the examination of type-material and published descriptions. We consider 7 of the 10 previously described species to be valid. Some characters, such as depth of the posterior notch of the body, which were used previously to discriminate between species of Capsaloides, appear to be questionable. Careful examination of type-material has led us to propose that C. istiophori, C. marielenae and C. tetrapteri are synonyms of C. perugiai. The possibility that C. cristatus and C. hoffmannae are synonymous with C. sinuatus is also discussed.

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