VOL. 97, PART 1 28 FEBRUARY, 1973 TRANSACTIONS OF THE ROYAL SOCIETY OF SOUTH AUSTRALIA INCORPORATED CONTENTS Alley, N. F. Landsurface Development in the Mid North of South Australia 1 Edmonds, S. J. Australian Acanthocephala, No. 14. On two species of Parar- hadinorhynchus, one new - - - - - - - ibs} Edmonds, S. J., & Jamieson, B. G. M. A new genus and species of earthworm (Megascolecidae: Oligochaeta) from South Australia - = 23 White, T.C.R. Aerial Dispersal of Adult Cardiaspina rs SORES: Psyllidae) in South Australia - - 29 Watson, G. F., & Martin, A. A. Life history, larval morphology and pee eostips of Australian leptodactylid frogs - - - - es Mitchell, F. J. Studies on the Ecology of the seecAge, Lizard Amphibolurus maculosus (Mitchell) - - - - - - - 47 PUBLISHED AND SOLD AT THE SOCIETY’S ROOMS STATE LIBRARY BUILDING NORTH TERRACE, ADELAIDE, S.A. 5000 LANDSURFACE DEVELOPMENT IN THE MID NORTH OF SOUTH AUSTRALIA BY N. F. ALLEY* Summary ALLEY, N. F., 1973. Landsurface Development in the Mid North of South Australia. Trans. R. Soc. S. Aust., 97 (1), 1-17, 28th February, 1973. The landsurface of the Mid North has resulted from a complex tectonic and erosional history. During the Cainozoic, faulting formed large basins in which terrestrial and marine sediments were deposited. The earth movements also initiated two major phases of erosion. Remnants of a landsurface established in (?) pre-Tertiary times are found high in the relief as weathered hills and plateaux in places capped by laterite (laterite surface). A probable mid Tertiary phase of planation is represented by silcrete capped remnants (silcrete surface). It is underlain by deeply weathered bedrock and occurs only a few tens of metres below the laterite level. The present broad valley floors, wide intermontane plains and coastal plains (plains and valley surface) had developed by the Late Quaternary. Etch surfaces are found adjacent to remnants of the two earlier surfaces. There is considerable structural control of landforms. Resistant quartzites and sandstones form the highest parts of the relief, as they also did during previous phases of erosion. Argillaceous strata have been eroded to form broad valleys, which follow the regional meridional strike. Differential erosion of these contrasting lithologies, combined with stream piracy, has led to the development of a trellised drainage system. The River Broughton is the only stream, which has maintained its westerly, consequent course throughout the Cainozoic, but stream captures have led to large changes in the drainage patterns of the Light and North Para Rivers. LANDSURFACE DEVELOPMENT IN THE MID NORTH OF SOUTH AUSTRALIA by N. F. Avitey* ALLEY, N. F., 1973. Lundsurface Development in the Mid North of South Australia. Trans. R. Sov. S. Aust., 97 (1), 1-17, 28th February, 1973. The landsurface of the Mid North has resulted from a complex teclonic and erosional histary, During the Cainozoic, faulting formed large basins in which terrestrial and marine sediments were deposited. The earth movements also initiated {wo major phases of erosion. Remnants of a Jandsurface established in (?) pre-Tertiary times are found high in the relief as weathered hills and plateaux in places capped by laterite (Jaterite surface). A probable mid ‘Tertiary phase of planation is represented by silcrete capped remnants (silcrete surface). It is underlain by decply weathered bedrock and ocevrs only a few tens of metres below the laterite level. The present broad valley floors, wide intermontane plains and coustal plains (plains and valley surface) had developed by the Lute Quaternary, Etch surfaces are found adjacent to remnants of the two earlier surfaces, There is considerable structural control of landforms. Resistant quartzites and sandstones form the highest parts of the relief, as they also did during previous phases of erosion. Argillaceous ‘strata have been eroded to form broad valleys which follow the regional meridional strike. Differential erosion of these contrasting lithologies. combined with stream piracy, has led to the development of a trellised drainage system. The River Broughton is the only stream which has maintained its westerly, consequent course throughont the Camo zoic, bul stream captures have led to Jarge changes in the drainage patterns of the Light and North Para Rivers, Introduction The Mid North forms an area of moderate relicf between the fold ridges of the Flinders Ranges to the north and the upfaulted plateau of the Mt. Lofty Ranges to the south (Fig. 1), The occurrence of fluyio-lacustrine and marine sediments on ridge tops, along river valleys and in structural basins indicates that this Tegion has had a complex history. Remnants of weathered tesiduals capped by laterite or sil- crete provide further evidence of this com- plexity. It is the purpose of this paper to trace the sequence of geomorphic events which Jed to the formation of these features and their Preservation in the present Jandscape. Geological Setting The Adelaide System Rocks The northern part of the area is underlain by Willouran, Torrensian and Sturtian strata (Wilson 1952; Clare 1 : 63, 360 sheet; Forbes 19651). These rocks are arranged in en echelon folds in the northwest but parallel folds oceur in the east (Fig. 1), South of Riverton faulting has resulted’ in the termination and breaching of the folds (Kapunda 1: 63, 360 sheet; Truro 1:63, 360 sheet). The Kanmantoo Group occurs here and is underlain by a sequence of Lower Cambrian sediments (Coats 1960*). importance af Lithology and Faulting The major topographic features. reflect the contrasting rock lithologies. Between Clare * Terrain Sciences Division. Geological Survey of Canada. Present address, Soils Division, B.C, De- partment of Agriculture. Kelowna. British Columbla, Canada. Research carried out at the Universily of Adelaide. 1 Korbes, B. G. (1965).—The ecology of the Clare 1: Mile area. Unpublished report, Geological Survey of South Australia. * Coats, R. P. (1960).—The geology of the Kapunda—Truro Military Sheets,.An explanation of the Geological Maps. Unpublished report, Geological Survey of South Australia. 2 N. F. ALLEY SOUTH AUSTRALIA BARUNGA R ANGE —_—— —— \ Narridy 2 Yacka Gorge 3 Spalding Gorge 4 Nantowarra Hills --7- Approximate dip and strike of bedrock | OKm 15 [ere Fig. and bedrock structures are shown. and the Murray Plains, the Gilbert Range Quartzite underlies the major ridges whereas dominantly argillaceous strata underlie the valleys (Fig. 5). Apart from the quartzite ridges, fault scarps form the most important physiographic breaks. The most conspicuous of these is one resulting a Baloklava Lr -s- - Vy ty 4 h t 1 ' 4 7 1 ' ' ' ‘ ' ! ‘ i r] ' 1 ‘ ' i ! 1 / t 7 © Spalding ' ' ' ' 4 4 \ 4 rk 4 1 ' ‘ I i ' t \ 1 ' ' 1 rt ' ' 1 \ ro i \ 1! ' t 1 \ ‘ a ! 1 ' 1S i toy rope 4 e +; F 4 af | r\o4 tak U { ert rl \ too) 4 te 1 nS Ul 1 1 : {oa \ 1 \ x 1 oo p M\er 1 \ a 5 re 2 fon ey 1 1 ‘oa ‘ rm) ‘ 1 i) o ! 1 ‘ aw} = F a br 1 ‘ \ & 1 ft | = a ! rc) t 1 ' Undalyay - bs 1 \ a fy *Riverton 1. Location, points of reference and general siruciure of the Mid North, Only the major faults from movements along the Alma Fault west of Clare, This fault and others divide the Mid North into a series of north-south trending blocks (Fig. 1). The youthfulness of many scarps and the scismicity of the area (Sutton & White 1968) suggest that the faulting con- tinues. LANDSURPACE DEVELOPMENT IN 'THE MID NORTH Cainozoic Sediments Although Tertiary marine strata abut the eastern and western flanks of the ranges, terres- trial sediments of similar age occur in several basins and valleys within the uplands (Table vr |). Two of the most important of the latter are the Wakefield and Barossa Basins, Buried beneath the sediments in these basins is a partly dissected, weathered and faulted Jand- surface, TABLE 1 Terrestrial Sediments of the Mid North Name Unnamed Description and occurrence Mottled and calcareous red sandy-clays. Found in major river valleys. intermontané basins and coastal plains. Age (7) Pleistacene tao Early Recent Koolwnga Gravels and siticified sands and gravels Rowland Flat Sands Flavio-lacustrine sands, gravels and boulders widespread in the Broughton caichment par- ticularly en the castern margins of the Wakefield Basin. Fluvio-lacustrine sands and. gravels found in the Barossa urea. Lignitic at depth in the Barossa Valley, Snowtown Sands Interbeddéd fluvio-lacustrine and ligniies found below Plains. sands, clays the Condowte Clinton Coal Late Tertiary to Quaternary Miucene Mincene Middle-Upper Measures estuarine origin, Confined to the Wakefield Ecocene Basin, A. PLUVIO-LACUSTRINE AND MARINE Middle-Upper Eocene beds (Harris pers. SEDIMENTS comin, 1968). The Miocene strata are 1. WAKEFIELD Basin The pattern of faults. demonstrate that the busin ts of tectonic origin (Fig. 1). As it forms the northern apex of the St. Vincent Basin, the periodic earth movements and subsequent sedimentation evidenced in both are necessarily related, Deeper Basin Sediments Bores drilled through the Inkerman-Bala- kKlava and Whitwarta coal measures penetrated a considerable thickness of estuarine (Harris pers, comm. 1968), marine and lacustrine de- posits. (Johnson 1959; Hillwood 1960). The sequences of the Balaklava area are complex and interpretation of the deposits. in particular the estuarine lignites, is uncertain, However, recent studies refer the latter to the Middle- Upper Eocene (the Clinton Coal Measures of Hartis 1966), und the overlying marine beds to the Oligo-Miacene (Hillwood 1960). ‘The northern and eastern limits of the marine beds lic along the Bowmans and Mt. ‘Templeton Fuults. At Snowtown the marine deposits are absent but interbedded carbonaceous clays, sills und sands of Miocene age overlie the lacustrine and terminate in the south along the Balaklava Fault, Because of their stratigraphic relationship to the Early Tertiary beds and their dominantly sandy lithology, the Miocene strata are separaled from the former and here named the Snawrown Sands, The type section is from stratigraphic borehole 4A on the northern edge of Snowtown and the strati- graphic relationships are shown in Figure 6. ‘The mid Tertiary marine sequences and the Snowtuwn Sands are separated from each other by «a horst, known as the Nantawatra Hills, which resulted from uplift along the Bowmans and Balaklava Faults {Fig. 1). The absence of the Oligo-Miocene sediments from the sur- face of the horst and their occurrence at the foot of the bounding fault scarps on the north and south suggests that the faulting predates the Middle Tertiary. Marginal Sediments Numerous deposits of highly siliceous sands and gravels occur along the fringes of the Wakefield Basin. Small outcrops abut the eastern front of the Barunga Range but Jarger deposits occur in the valley of the River Broughton on ihe eastern edgé of the basin. N. FL ALLEY & 4 Gulnare Fluvios (ucustrine deposits. _- Surface exposures of the ~ 4) Koolunga Gravels : Uplands, OKm 5 —— ‘Alma Fault 2. The distribution of the Koolunga Gravels in the middle and upper Broughton drainage basin. The dips. of the faults in the Mt, Gregory Range are unknown, The most prominen| crop out near Koolinga. Yacka and Spalding (Fig, 2). These deposits are here named the Koolungu Gravels and the lype section is located at White Cliffs, 4 km east of Koolunga in the south bank of the Broughton River (Fig. 10). The western edge of the Koulunga Gravels is marked by a low rise which may represent the northern extension of the Owen Fault Scarp, for bore logs indicate that they continue al depth further westwards. At White Cliffs the gravels overlie an. itregular surface eroded across Precambrian bedrock (Fig. 10). Move- ment along a fault zone in the latter has led toa J m dislocation of the overlying deposits. The best exposure of the beds occurs in the Yucka Valley where deltaic sands and gravels containing boulders of silcrete overlie gently dipping Precambrian sandstone. These deposits can be traced across the ridge marking the western flank of the valley, but the Alma Fault scarp separates them from the Koolunga sequences (Fig, 2). Because of their similar pebble lithologies, in particular the presence of silerete in both, the Yacka and Koolunga beds were probably deposited contempor- angously and have since been displaced by faulting with the downthrow to the west. Whether the highly siliceous gravels south and cust of Spalding were deposited in the same lake is a matter for conjecture, for they stand 100 m higher than those at Yacka (Fig 2). The difference in height between the two deposits may reflect a fallmg lake level or fault- ing, or the Spalding gravels may not be corre- lative with the Yacka heds and instead be en- tirely fluviatile, However, the presence of xilerele houlders in the Spalding gravels indi- cutes that they may have been deposited con- temporaneously with the Koolunga Gravels. Although no fossils were recovered from the Koolunga Gravels, there 1s evidence to suggest that they post-date the mid Tertiary, At White Cliffs and Yacka the gravels contain boulders of silcrete. a rock assigned lo a probable Middle IT ANDSURFACE DEVELOPMENT IN THE MID NORTH 5 Tertiary weathering phase (see below). North and west of Yacka, outcrops of the gravels overlie an etch surface related to the erosion nf the silcrete surface (Fig, 3). Thus, the Koolunga Gravels do not represent a shoreline facies of the Snowtown Sands but were de- posited at different times in a Jake occupying the same basin. Silerete & ~koolunga a Gravels (exhumed } Fig. 3. The stratigraphic relationship between the Koolunga Gravels und the silcrete surface in the Yacka area, Only the sur- face exposures of the gravels are shown. 2, Bakossa Basin These include the fluvio-lacustrine sediments deposited east of the Para Fault in the Barossa and Stockport-Freeling areas (Pig. 4). The strugture of the Barossa Valley is not completely Known. Tt has been described as a graben (Hossfeld 1949), a Fault angle valley (Chuge 1955), and an asymmetrical synctine with q fault or flexure along the southeastern flank (Dalgarno 19613; Olliver 1962). Never- theless, the nature of the Tertiary strata ¢on- tained by the valley is well documented (for a review of this work see Dalgamno 1961, and Harris & Olver 1965). West of Rowland Flat a basal deltaic unit is overlain by a sequence of sands and gravels characterized by medium und Jarge scale deltaic bedding (the Rowland Flat Sands Conglomeratic Lens and the Row- hind Flat Sands of Dalgarno 1961), whereas lignitie sands have been encountered at a depth of 30 ta 100 m during boring in the Rowland Flat-Tanunda plain (Chugg 1955), As there is no stratigraphic evidence for scpurating the conglomeratic lens from the overlying sands, it is proposed that it be in- cluded as part of the Rowland Flat Sunds. Scattered outcrops of the sands extend west- wards across the Kitchener Fault to the Gawler area, and northwards to Stockport (Fig. 4). They were probably deposited contem- porancously with the Rowland Flat Sands as the beds occur within the same range of eleva- tion (Fig. 4). Moreover, the Lyndoch-Sandy Creek deposits ure characterized by the same mineral assemblage as those at Rowland Flat and are thus regarded as the westerly extension of the Barossa sequences (Olliver & Weir 1967). Although the Rawland Flat Sands. have been assigned a variety of ages, recent palynological evidence indicates « Miocene age, making them time correlative with the deposits northeast of Gawler (Haris pers. comm. 1969). B. ALLUVIAL DEPOSITS Red alluvium covers most of the low-lying iireas, varying from a Tew metres in minor creeks to 36 m in depth at Balaklava. In the Barossa Valley and near Red Ranks, bores show that the sandy clays exceed 30 m in thickness. Although the alluvium is 15 m deep in the Yackamoorundie Valley downstream from Georgetown, it rarely exceeds 6 mm in the upper reaches of other main Valleys, In most areas the alluvium is mottled and calcareous, Suggesting some measure of weathering since its deposition. The alluvial clays are interpreted as a Pleistocene deposit in the Port Wakeficld area (Johnson 1959; Hillwood 19640; Horwitz 1961) 7 Dalgarno, C: R. (1961}—Geology of the Barossa Valley. Unpublished M.Sc. Thesis. Universily of Adelaide. 6 N. F. ALLEY Sandy Creek "215 Spot Height imetres! Q cnt 266 Para Fault Fig. and the Burossa Walley (Campana 1955; Chugg 1955). On the basis of radiocarbon dat- ing, the red clays. north of Adelaide have been assigned to the Late Pleistocene (Williams 1969}, Mottled clays (the Hindmarsh Clay of Firman, pers. camm, 1968), overlying a Plio- cene marine bed at Red Banks are believed to be of Pleistocene age. On this basis the heavily calcified red clays in the Mid North have been placed tentatively fee 5 lyndoch, SS sKAPUNDA -—— Moin uplands =| Rewland Flat : Sands (sic. exo.) 4. The distribution of the Rowland Flat Sands in the Barossa-Freeling area. The differences in height of the deposits in the latitude of Freeling may be related to post Miocene earth move- ments, in the Pleistocene to Early Recent though they may vary in their precise age or age-range from locality to localily. C, WEATHERED LAND SURFACES BURIED BENEATH THE CAINOZOIC SEDIMENTS In the Snowtown area only a few bores penetrate to the Precambrian but these reveal that the basin floor is irregular and weathered. LANDSURFACE DEVELOPMENT IN THE MID NORTH 7 At a depth of 69 m, stratigraphic bore No. 4A located at Snowtown, penetrated 27 m of highly weathered sandstone, Three kilometres north of Snowtown unweathered bedrock occurs at 49 m, but Icss than 1.5 ko east of this location the basin floor deepens to 111 m.. { f OMintate f a - ep © ‘The weathering of the basement rocks probably predates. the deposition of the overlying Ter- tiary sequences for bore logs indicate that the latter are essentially unweathered, The nature of the buried surface beneath the Rowland Flat Sands is better known. Bore logs Q Merildin S lerete leyrmeants ¥e8 +566 Spot height (r = OWotervale a Gilbert Ronge Quartzite Weathered residual) and etch plains related to the laterite level =— Loierite level ea Fig. 5. Remnants of the laterite and silcrete surfaces near Merildin. The Gilbert Range Quarizite underlies the major ridges, while dominantly argilliceous strata crop out in the valleys.” + WN, F. ALLEY indicate that the basement rocks are weathered in the Barossa Valley (Chuge 1955). At Row- land Flat the unconformity surface has a local telief of up ta 15 m (Olliver & Weir 1967) and the Rowland Flat Sands overlie both fresh and weathered bedrock (Fig. Ll). At ©. R, Hueppau!’s quarry, on the north bank of the North Para River, Torrensian bedrock is weathered and highly ferruginized. Between Sandy Creek and Warpoo Siding, highly kuolinized mica schist underlies the sands. South and west of Frecling the sands were de- posited on subhorizontal bedrock surfaces, though only small remnants of the Tertiary sequences remain. Thus it appears that the Rowland Flat Sands were deposited on a partly dissecied erosion surface underlain by highly weathered and ferruginized bedrock. Surfaces uf Degradation and Deposition Investigations reveal that remnants of three major surfaces of erasion and deposition occur in the Mid North. The highest and oldest of these is capped discontinuously with laterite. Below this is another erosional surface which supports a thick crust of silcrete, The youngest surface ls largely depositional and the alluvial clays underling it ure heavily calcified, Etch plains of considerable extent developed as a result of the dissection of the laterite and sil- crete surfaces, Larertte Surface Apart from the prominent ridges underlain by quartzite and sandstone, remnants of the laterite surface form the highest parts of the lajdscape. Where, the laterite truncates thick Precambrian argillaccous strata, slopes vary belween 1° and 2° (Fig, 12), However, near the quartzite ridges remnants of pediments exhibiting slopes of up to 7° are found, Such residuals are common in the ranges euse of Clare (Fig. 5) and Riverton, Remnants of the laterite surface are more numerous at the streum) Heads. Nevertheless, by virtue of their resistant capping they alsa fonm prominent. hills standing nearly 100 m above valley floors. yome distance from the ridges (Fig. 13). The laterite capping, which consists essen- tially of angular quartz set in a matrix of tron oxides, is underlain by heavily weathered and locally kaolinitic bedrock (Fig. 14>. Only the massive quartzites and sandstones remain uny- altered and these stand 30-180 m ubove the general surface level) A zone of intense weathering often lies at Ihe head of the pedi- {nent Férnnants Which slope away from these scarps wheras the Jaterite crust is consistently thickest on the lower slopes. The etching away of the weathered strata from beneath the laterite has let to the exposure of broad bedrock surfaces, It is usually the case that these etch surfaces lie 15-30 m below the laterite surface and separated from it by seep scarps. Because of strong lithological control during weathering and subsequent erosion, the etch surfaces are often irregular with argillaceous strata forming the vallevs, and sandstones the ridges (Fiz. 13), Silerete Surface Evidence of a former erosion surface capped by silcrete and consistently lower than the height of the faterite is found throughout the Mid North (Fig. 15). It reaches its optimum development around the northeastern fringe of the Wakefield Basin (Fig, 6), Here slopes can be less than 1°” whereas slopes as great a8 4° have heen encountered elsewhere. Like the laterite, the silerete surface truncates rocks of ull types, except the thick quartzites, and 1s Underdain by some 15 m of intensely ksolin- ized bedrock. North of Narridy the weathering reaches a depth of 30 m, bul this is probably duc to the porosity of the underlying sandstonc. Fertuginuus hurtzuns are common in the weathered zone developed across argillaccous strata (Fig, 7), ‘The nature of the silerete crust is variable (Figs. 7, 16). Higher parts of the surface are weakly silicified or suppart a thin capping of consolidated regolith. Silcrete lower in the relief is generally thicker und finer grained, In many areas where the silcrete has heen broken up. a thick lag of boulders remains as a pro- tective veneer over the weathered bedrock, An extensive etch plain developed following dissection of the silerete surface, particularly where the main streams cut deep gorges through the silercte level. Thus prominent bed- rock benches occur slong the Rocky Rivet downstream from Gladstone and the Yacka- moorundie Creek west of Gulnare. This sur- face is often capped by a silicificd congtom- erle containing Lragments of silcrete derived from adjacent silcrete remnants (Fig, 17), Because the conglomerate has all the charac- |_ANDSURFACE DEVELOPMENT IN THE MID: NORTH 9 N 4 4 7 4 i] qt = 4 1 oBurra _ 4 | Murray Laterite Bid: ans remndnts dominate Largely silcrete remnants oy Areas farming probable Miocene lake basins ~ ~ 3 o -~ s Gkm | ce | << = cr 2 f as DGawler-—-E= —— ras Leterjte Nantawarro Hills A a i Silcrete S a Lote Quaternary alluvium ~*< = =a = ee S 3 2 \ = Weathered Pre £ ~ ri ~~, “ ee dn Balaklava Fault Fig, 6, The distribution of laterite and silcrete remnants in the Mid North, and the stratigraphic re- lationship between the surfaces bordering the Wakefield Basin. The diagrammatic section (not to scale) has been constructed from bare logs. From the surface, 1$ m of plains and valley alluvium are underlain by 15 m of silts and clays, 23 m of Miocene Snowtown Sands and 35 m of Middle-Upper Eocene Clinton Coal Measures (E). Both the latter units vary consider- ably in thickness, The Mt, Templeton Fault occurs in the breached part of the section. (a N. F_ ALLEY Raolinized “ sondstone , f ‘gin oF, tren oxides a | fr 3. West of Kupunde Fig, 7. Variations in the silcrete crust and its underlying weathering profile in the Mid North, Section 1: Zone A consists of pisolitic silcrete; B laminar sitcrete; C is a com: plex zone grading downwards from sili- cified sandstone to very resistant por- celanitic silcrete. Section 2: Zone A, massive crypto- crystalline silerete; B, weakly silicified sandstone; C, very weathered rock con- tuining abundant angular fragments of quartz. Section 3: Zone A, massive crypto- crysialline silercte containing numcrous rounded quartz pebbles near its base. teristics of a sedimentary rock and uncon- formably overlies fresh Precambrian at numerous sites, it is not interpreted as a second period of silcrete formation and is referred to as silicified sands and gravels. On the basis of its relationship to the etch surface these sedi- menis were probably deposited in valley bottoms contemporancously with the Koolunga Gravels. Relative Ages of the Laterite and Silcrete The laterite surface forms the flat upland of the Nantawarra Hills (Fig. 6), To the ease and north of the hills, the surface has been downfaulted and the Middle Tertiary sedi- ments occur at the base of the fault scarps suggesting that the laterite surface in this areca may be Early Tertiary or older, In this case, the surface buried beneath the Middlc-Wpper Eocene lignites in the Snowtown region could be the equivalent of the laterite surface, On the other hand, if the lateritized surface un- derlying the Rowland Plat Sands is correlative with the laterite surface, the Jatter must have persisted in the Barossa area until the mid Tertiary when earth movements led to its dis- section and partial burial. ii is difficult to assign an age range to the silerete surface, although mapping reveals that it is consistently Jower than the laterite surface even where they truncate the same strata (Fig. 8), Thus the difference in their heights is due to crosion rather than Jithology, and it can be inferred that the silerete is younger than the laterite surface. However, the optimum de- velopment of the silcrete surface occurs around the fringes of the Wakefield Busin, There is evidence lo suggest that the early ‘Tertiary Fig. 8. The altitudinal relationship between the laterite and silcrete: surfaces west of Georgetown. The bedrock strike is approximately north-south, ard both surfaces are eroded across the same strata, LANDSURFACE DEVELOPMENT IN THE MID NORTH It esluatine swamps and then the Miocene lake which occupied this basin may have formed the base level af erosion for the silcrete sur- face in the surroundiig area, First, the surface slopes vently towards the basin. Second, the Eocene estuarine and the Miocene Jacustrine sequences are generally fine, suggesting that deposition Was cantemporaneous with the ero- sion of a plain of low relief which is consistent with the gentle slopes observed on the silcrete remnants, Third. no silcrete is recorded from the borcholes drilled through the Tertiary secliments, Present Valley Floors and Plains The must extensive surface of ageradation in the study area is the Condowie Plain (Fig. 1), Near Snowtown the plain measures almost 4 km from east to west, whereas in the noflbern part near Redhill the basin is Jess than § km wide. The Condowie Pliin con- tinkes southwards and gradually merges with the Adelaide coastal plains south of Baluklava. In the latitude of Snowtown the surface of the plain is gently undulating but asymmetrical wilh a long. fall from the Alma Fault scarp on the east. No streams traverse the plains excep! along the northern fringes: Where the Broughton and its two lurge tributaries, Rocky River and Yackamoorundie Creek, are incised up to 9 m in the red alluvium. Two other intermontane basing oceur: the Barossa Valley and athe Yackamoorundie Valley south of Georgetown, the later con- twining an alluvial fill 54 m in depth. The surfice of the Barossa is similar to the Con dowie Plain. displaying east-west asymmetry. Broad alluvial Fans front the Barossa Ranges near Rowland Plat, gradually giving way to a gently sloping surface further north. Along the westerh edge of the basin the plain extends across aulcrops of the Rowland Flat Sands as a lightly ferruginized erosional surface. Age of the Plains and Valley Supfice Vhroughout the Mid Novth, the red cal- carcous clays are the most common deposits underlying the surface. This alluvium has been assigned a Pleistocene to Recent age (see above), and thus the surface must be approxi- mately the sume age, In the Barossa where it (runciles the Middle ‘Tertiary lake sediments, portion of the surface may belong to the Late ‘Terriary Development of the Drainage System The Mid North is drained by two sets of river systems: the Broughton, flowing to Spén- cer Gulf, and the Wakefield, Light ani North Para Rivers. to St. Vincent Gulf, The history of change in this drainage pattern can be determined by an examination of the nature of the Tertiary sediments and landsurfaces. A. INFLUENCE OF LITHOLOGY AND STRUCTURE The perfection of lithologies) adaptation of the drainage is a feature of the area. In broad view lithology determined the direction of drainage on the two duricrusted surfaces, Once the weathered mantle was removed from these surfaces. intricate irregularities in lithology controlled the course of erosion. Consequently, the present drainage exhibits 4 trellised pat- tern, the long subsequent (strike) streams flowing in valleys underlain by argillites while the resistant sandstones and quastzites remain as the fidges. The north-south trending prat- fern of the major streams results from = the meridional strike of the fold axes (Fig. 11. B. CHANGES IN THE PATTERN DURING THE CAINGZOIC The long meridional trending reaches of the strcams have heen interpreted as the dismem- bered drainage of a Tertiary peneplain (How- chin 1933; Hossfeld 1935; Langford-Smith 1949), Such a postulate may only be applied to the St. Vincent Guif drainage. 1. Tie River BroucHTon Based on the evidence of elbows of capture, abandoned valleys containing riverine graveis and increased gradients in the gorge sectors of the newly formed valleys, Langford-Smith (1949) demonstrated that stream piracy occurved amongst minor tributaries in the Jumestown area. In view ol the elbows and gorges slong the Broughton, he applied the theory to the whole drainage basi, He pro- posxd that the river captured a system of southerly flowing streams from ihe west sub- sequent upon uplift of a Tertiary Jundsurface. Faulting aided local ponding of the stream and hastened the speed of capture. However, investigations cannot substantiate the theory. Only two gorges occu’ along the Broughton, ohne west of Yacka and the other west of Spalding, No knickpoini is found in the Yacka reach while those in the Spalding gorge fesulk [rom lithology or structure. There is no 2 N, F. ALLEY evidence of a former south flowing stream system, the development of which was pro- hibited by the geologic structure of the arca and the resistance of the Gilbert Range Quart- zite, Upstream from Yacka the drainage pat- tem may have been in existence since Early Tertiary times, for remnants of the laterite surface slope towards major streams whereas their heights decrease down-valley in the direc- tion of present drainage. Many of the Caino- zoic gravels, some of them lacustrine, occur both on intervening ridges and in several gorges, instead of only in the broad strike valleys, As uplift of the Tertiary landsurface occurred along N-S trending faults, there should have been no local impounding of south flowing rivers. Moreover, the disposition of the Cainozoic sequences in the Yacka-Spalding area suggests faulting after depositton, not be- fore. Finally, if stream piracy has occurred, it is the Broughton system which is being cap- tured not the reverse (Fig. 9}. The middle and upper reaches of the Broughton have remained essentially unmodi- fied and it is only downstream from Yacka é *Menldin . Stream capture of the upper Farrell Creek near Merildin. The nature of the barbed drainage within the enclosed sec- iron and the pronounced elbow of the Wakefield downstream from Merildin indicates. that the pirate stream was the River Wakefield. that the evidence suports changes in the put- tern. Focene. lignites extend at depth to within a few kilometres of Koolunga where the Broughton turns north-westwards to flow across the northern perimeter of the Condowie Plain. If the upper reaches have altered little since the Early Tertiary, it is logical that the river made its way to the present St, Vincent Gulf area through the tectonic yalley which came into existence at this time (sce aboye), lt is probable that uplift of the Nantawarra horst in the mid Tertiary blucked the valley, leading to the formation of a lake, A larger lake resulting from reactivation of upwarping in the Late Tertiary or Quaternary either over- flowed the Baruhga Range or was captured from the west (or both) and the Broughton fiowed into Spencer Gulf. 2. St, VINCENT GULF DRAINAGE A striking feature of the drainage pattern of these rivers. is the absence of major south bank tributaries (Fig. 1), An eaamination of the Cainozoic sediments and the Tertiary land- surfaces reveals that only stream piracy can account for the anomaly. The long quartzite ridge east of Tarlee was a major drainage divide in Early Tertiary times. All laterite remnants slope away frem it as far north as Manoora and south as Green- ock, Erosion of this surface by separate drain- uge systems is indicated by large diiferences in the height of residuals on opposite flanks of lhe ridge. The river east of the ridge occu- pied the valley of the upper River Light und flowed southwards along the present Barossa Valley area whereas the other approximutely paralleled the course of the Gilbert River. However, there ts no evidence to suggest that the River Wakefield had yet been established. Consequent upon the mid Tertiary earth movements were the dissection of the laterite surface and the formation of a Jake in which the Rowland Flat Sands were deposited. The two south flowing streams probably enterudd the lake at the northern edge of the Barossa Valley and near Stockport. This is borne owt in these areas by the coarseness of the gravels, the palacocurrents and the mineral assemblage (Dalgarno 1961, Alley 19694). In Late Cainozoic times the majar stream east of the divide was captured from the west LANDSURFACE DEVELOPMENT IN THE MID NORTH 13 by two separate streams, one forming the present lower reaches of the River Light now confluent with the Gilbert River, and the other, the North Para River. Stream piracy is supported by several lines of evidence, First, prominent elbows occur on the rivers where they turn westwards to flow across the strike of the bedrock (Fig. 1). Second, an abandoned valley due south of Rowland Fiat and infilled with Tertiary sediments may represent the former channel of the beheaded stream. Third, hoth portions of the newly formed streams have cut deep charinels into the Rowland Flat Sands, suggesting that the excavation post-dates the mid Tertiary, Although a prominent elbow occurs en the River Wakefield at Undalya, where the river turns into a gorge and flows across the strike nothing other than the lack of major south bank tributaries to suggest that capture may have taken place, Landscape History Remnants of three major Jandsurfaces have been described and discussed (Table 2). Since the dissection of the Jaterite surface, differen- tial erosion has led to increasing relief. Where the ridges formerly stood 90 to 180 m above the level of the laterite surface, they now pro~ ject more than 300 m above valley floors. Early Tertiary earth movements in and around the Wakefield Basin probably led to the disruption of the laterite surface in the Broughton drainage system and the establish- ment of a new phase of erosion during which of extremely resistant TABLE 2 Surfaces in the Mid North quartzites, there ts the silcrete surface developed. Broad etch sur- Surface Plains and valley Description and origin Major valley floors, intermontane basins and coastal plains, Narrow. erosional pied- mont zone fringing these areas, Mainly aggradational. Unweathered bedrock surfaces ‘standing below and adjacent to the silcrete surface in the Broughton catchment. Developed subsequent te removal of weathered zene beneath the silérete, Buried by lacusitine gravels in some localities bul exhumed jn others, Probable age Late Tertiary (7?) to Early Recent Initiated in the Late Cainzaic Silcrete Silicified mesas and valley sides occurring throughout the Broughton catchment. fso- lated remnants near Kapunda, Freeling and Owen. Resulted from erosion and weather- ing. High unweathered bedrock benches devel- oped below and adjacent to the laterife sur- face as a result of removal of the weathered mantle from below the laterite. Laterite Broad plateaux and mesas capped by later- ite and, apart from quartzite ridges, form- ing the highest parts of the relief. Resulted from erosion and weathering. Mid Tertiary Initiated in the Early Tertiary {7) Early to pre Tertiary. Persisted to mid Tertiary in the Barossa area. faces resulted from the removal of the deeply weathered muntle much of which was de- posited lower in the relief as. the Middle-Upper Eocene sediments, and later in the Miocene as the Snowtown Sands. The laterite surface persisted in the Barossa area until the mid Tertiary when renewal of the faulting led to its dissection, The earth movements probably dammed streams, leading to the formation of a basin in which the Rowland Flat Sands ac- 4 Alley, N. F. (1969).—The Cainozoic history af the Mid North of South Australia. Unpublished M.A. Thesis, University of Adelaide. 14 N cumulated, As these sands and the Snowtown Sands are contemporaneous but deposited in separate tectonic basins, it is logical to argue that the earth movements were widespread during the mid Tertiary, There is evidence to suggest that the fault- ing continued, In the narth, earth movements account for the dissection of the silcrete sur face, the development of broad etch plains and the deposition of the Koolunga Gravels con- temporancously with the silicified sands and gravels. Recent earth movements were respon- sible for the dislacation of the Koolunga Gravels at White Cliffs and in the vicinity of Yacka. Deposition of the plains and valley alluvium and the alluviul fans abutting the Alma and Kulpara Fault scarps may also have heen initiated during this period. If the buried surfaces beneath the Tertiary sediments in ihe Wakefield Basin and the RB ALLEY Barossa Valley are analagous to the Jaterite surface, it has suffered faulting or warping in the order of 300 and 180 m respectively in these areas. Acknowledgements The thanks of the writer are due to: the South Australian Department of Mines for making bore Jog data and unpublished reports available; Mr. W. K. Harris, 8, Aust. Depart- ment of Mines, for his advice on the Tertiary stratigraphy; Mr. A. R. Milnes, Department of Geology, University of Adelaide, for his guidance in the analysis of the duricrust pro- files; Mr. M. J, C. Walker, University of Edin- burgh, for his critical reading of the text; and Dr, C. R. Twidale, Department of Geography, University of Adelaide, for his valuable com- ments in the ficld and on this paper. References Camerana, B. (1955) —Lhe geology of the Gawler Military Sheet. Rep. Invest. geal Surv. §. Ast, 4, 1-22. Cuucs, R. — (1955)—The hydrology of the Rarossy Valley, Refi. Invest. geol. Surv. 8. Aust, 2, 1-77, Coats, R. P. (1959)—Trure map sheet, Geolo- gical Ailaus. of South Anstralia, 1763, 360 series, (Geol, Surv. 8, Aust.: Adelaide.) Dickmson, 8. B. & Coats, R. PB. (1957)— Kapunda map sheet, Geological Atlas of South Australia, 1:63, 360 scrics. (Geal. Surv. S. Aust.: Adelaide.) Fortis, B. G. (1964)-—Clare imap sheet, Geo- logical Atlas of South Australia, 1:63, 360 series. (Geol, Surv, S, Aust: Adelatde.) Harris, W. K. (1966) —New and redefined names in South Australian Lower Tertiury strut graphy. Quart. geol. Notes, geol, Sun § aust. No. 20. Harais, W. K. & Ouniver, J. G. (1965),--The age of the Tertiary sands at Rowland Fiat, Burossa Valley, Quart, geal. Notes, geal. Sarv. 8, Aust. Na. $3, Hitt woop, E. R. (1960)—Inkerman-Balaklava coalfield, Min, Rev. Adelaide 112, 26-46, Hoawitz, R. C. (1961).—The geology of the Wakefield Military Sheet. Rep. Invest. geal. Sary. §, Aust. 1B, 1-32, Hosseeep, P. S. (1935)—The geology of part of the north Mt. Tafly Ranges, Tras. R. Soc. S. Aust. 59, 16-67. Fie 1, At White Cliffs, 4 km cast af Koolunga, Late Cainozoic (7) Muvio-lacustrine sands and gravels containing boulders of silerete have been folded: The monoclinal fold (M) indicates that 4 to 5 m of displacement has occurred. The folding is of the posthumous type and hax resulted from movernents in the underlying contorted Precambrian phyllitic shalcs which upper in the lower left (P)-. Fig. |!, The irregular unconformity surface between the subhorizontally bedded, Miocene Rowland Flat Sands. and steeply dipping Precambrian schists in a quarry west of Rowland Flu, Fig, 12, A few kilometres west of Georgetown temnants of the laterite surface occur, Here the surface slopes gently away from an unweathered core of Precambrian rocks known us Mt. Herbert (right), The laterite crust is underlain by 2 to 25 m of kaolinized shales some of which can be seen forming the white areas on the flanks of the two residuals, Fig. 13. ML Allen. a lateritic, weathered residual eroded across green silty shales in the snout of a syjicline & km due north of Kapunda. The arcuate, low ridge covered by gums and almost sur- rounding Mt. Allen consists of unweathered Marinoan quartzite (A,B.C.7}. Differential ere- sion of adjacent weathered strata, has. accentuated the prominence of the ridge and resulted in an irtegolar etch surtace. 1s MID NORTH IN THE | ANDSURFACE DEVELOPMENT —— — | = ALLEY N. F. 16 NAYS male genital field (holotype); £, right prostate (paratype 2). Clitellum shaded. All hy camera lucida. 9, female pore; g.m, accessory genital marking: ¢, male pore; pr.d, prostate duct; pr.g, glandular portion of prostate; sp.amp, spermathecal ampulla; sp.d, spermathecal duct: sp,div, spermathecal diyerticulum; sp.p, spermathecal pore. Roman numerals ate segment num- bers, in V-XIII; those in X—XIII forming large latero-oesophageal hearts, each originating from the supra-ocsophageal vessel but also re- ceiving, at its junction with the latter, a slender short connective from the dorsal blood vessel; these hearts otherwise unbranched. Commis- surals in V-IX dorso-ventral only, lacking supra-esophageal connectives, but giving branches to the posterior septum, gut and lateral parietes; all commissurals, including the hearts, yalvular. A pair of Jarge vessels originating on the parietes in TV passes posteriorly as a pair of large ventrolateral trunks (latcro-oesophageal vessels), median to the dorsoventral. commis- surals, Into TX at the posterior scptum of which they give branches to the ventral wall ‘of the oesophagus and to the septum, Similar paired trunks (suboesophageal vessels) present in XI-XYIJ, closely adherent to the ventral surface of the oesophagus and lying under its peritoneum; no continuity demonstrable he- tween the latero-cesophageal vessels in IX an- ™ S. 1, ERBMONDS und B. G. JAMIESON teriorly and the suboesophageal vessels in XI posteriorly, both pairs of vessels give a pair of vessels to the nesuphageal plexus in each seg- mene. Submeural vessel absent, Gizzard moder- ately lurge, fusiform, and firrnty muscular in Vii septum 5/6 adherent to its anterior end: its posterior end projecting a little behind inter- segment 7/8; the ocsophagus much narrower in V, short and narrow in VIL dilated and vascularized with low intermal rugac, but ne calciferous glands, in VUI-XY, narraw and short in XVI Intestinal origin XVIL; a low ridgelike dorsul typhlosole commencing in XXIF, caeca and muscular thickening absent. Nephridia: meronephric: large paired tufts, with very many spiral loops, in I. IL. TV and V increasing in size pasteriad and very large in V. Those in V and IV sending antero- medianly thick sheaves of numerous ducts, which loosely aggregate ay 4 composite duct common to both pairs of tufts, the ducts pass- ing forward (to join the lateral wall of the buecal cavity in front of the brain, Those in Il and I sending slender composite ducts to the lateral walls of the buccal cavity immed- iately behind the muuth, Nephridia in succecd- ing segments astomate. exonephric, micro- meronephridia: very dense transverse bands of spital tubules, which laterally may be ¢on- sidered to form tufts, anterior in WI, their numerous discrete or partly aggregated ducts Hischarzing exonephrically at the anterior limit of the segment; some exonephric nephridia present! pasteriorly in the segment; VIT-X each with an anterior and a. posterior parietal band of numerous nephridia; XI, XU and XT with similar but rather sparse bands; XIV with sparse anterior and dense posterior bands; XV with Uenser unierior und sparse posterior bands; XVI (the last oesephages! segment) and succeeding intestinal segmests with only anterior hands; hands dense in XIV-XVI1L. Caudally, commencing at segment 120 (in holotype with [92 segments), with numerous enlarged onephridia (almost megamerone- phridia) in each segment on the anterior wall of the segment near to ard encireling the in- testine, the nephridia about five deep and cach with 4 long-slalkecl conspicuous. preseptal funnel, the nephridial ducts in cach segment Tunning medially as a common duct on each side to enter the wall of the intestine anteriorly in the segment on each side of the dorsal blood yessel, though some individual nephridial ducts reich the wall of the intestine independently in the vicinity of their nephridial hodies, Concen- tric with and external io the enlarged, entero- nephric nephridia are parietal astomate, apparently ¢xonephric, micromeroncphridia in dense transverse bands. The number of cn- larged nephridia decreases, and that of the micromeronephridia greatly increnses, m the last twenty or so segments. Holandric; sperm funnels iridescent in X and XI; Lestis-sacs absent; seminal vesacles large lobulated sacs im XI and XII; similar. smaller, structures on the anterior septum of X ate of unknown function but cannot be seminal vesicles. Ovaries (webs of large oocytes) and funnels in XIII; vvisics nbsent, Prostates limited to X VINE, flattened, Jobulateel S-shaped glands with short slightly tortuous muscular ducts joined near their ental ends by the vasa deferentia. Penial setac absent. Spermathecae 3 pairs, in VU, VII and IX. diveruculun (inseminated) single, subspherical. internally multiloculate, with a shert stalk (H, Ph). Field Variation: In 16. clitellate type-speci- mens. including the holotype, a lransvetse median genital marking is present in [5/16 and 16/17 in 9 specimens, and in 19/20) in fO specimens, Seven of these specimens have the Full complement. of markings, in 15/14. 16/17 and 19/20; 2 specimens have the geni- tal marking m 15/16 only; 2 have them in 16/17 and 19/20 only: 1 has a marking in 19/20 only; und 4 have no murkings, Murerial Exentined: Cudlee Creck, 34° 50°S_. 138°49°E,, from helow apple orchard of Mr. G. Newman, Edmonds, August 1971—H, PI-9; N, Maier, 21L.viti1972—PlI-s3. Hahndorf, 35°02'S., 138°48'E.. G. Perersan, 25.viii 1972—P 70-12. H, P2-4. deposited in the Australian Museum. Sydney; PL. 5, British Muscum (Natural Histury); P6. 7, South Australion Mailscuum; P8—-12 famieson collection, Remarky: Material used in undergraduate stadies and not retained cannot be designated type-material but. nevertheless, variation in it may be noted. In 50 specimens the length was 200-271) mim; the width was 7-9 min generally but 8-11 mm in the region of crop and gizzard. The clitelum embraced XIV-XVII hui some- times included part of MII and of XVIIL Numbers of spetmathecal pores and location of the male pores and of the female pore were constant. Accessory genital markings, when present, were usually at 15/16, 16/17 and 19/20, The iitestine usutaily began. iy XVI, a condition also noted in some nf the type- NEW GENUS AND SPECIES OF EARTHWORM 37 specimens. The flattened S-shaped form of the prostales was constant, The supra-oesophageal vessel occupied VII-X1V, ramifying on the oesophagus at each end, In one hundred speci- mens the number of segments was 155-198, The course of the suboesophageal blood vessels has not been unequivocally determined and, with that of the latcro-parietals, requires further examination. The structures resembling seminal vesicles anteriorly in X do not show spermato-genests in serial sections, whereas the seminal vesicles in XI and XII do. Gemascolex newmani is distinguished from the equally large Megascolex stirlingi, so fai as it is described by Fletcher, 1888, in (a) location of the spermathecal and male pores in ab lines whereas in M. stirlingi they are markedly more lateral, in setal lines 6 and be- tween setal lines 3 and 4 respectively; (b) the unpaired instead of paired accessory genital markings and their forward extension to inter- segment 15/16; (c) the S-shaped, not straight, prostates and in other respects. Noteworthy differences from MM. zierzi, as described by Michaelsen, 1907a, are (a) the more median location of spermathecal and male pores, (b) location of the male pores well lateral of paired accessory genital markings in M zietzi, (¢) presence of further paired mark- ings on the anterior border of the male poro- phores in the latter species; (d) restriction of the prostates to XVIII and their S-shaped form: (c) the subspherical sessile spermathe- cal diverticulum of newsani contrasted with the very Jong tortuous tubular diverticulum of M. zietzi. Acknowledgements The authors thank Mr, G, Newman for per- mitting collection of the new species from his property and Mr. G, Peterson and N. Maier for procuring additional material. This work was carried out during tenure of ARGC and URG grants, References Bani, K. Ny (1946).—Studies on the structure, development, and physiology of the nephridia of Oligochaeta. Part VII. The enferonephric type of nephridial system in carthworms be- longing to three species of Megusvolex Templeton and three. species of Travoscolides Gates (Meguscolides McCoy), Q. JI microse: Sei. 87, 45-60, FLeTcHer, J. J. (1888)—Notes on Australian earthworms, Part II, Proc. Linn. Soc, NSW. 2, 375-402. Jamirson. B. G. M. (1970).—A review of the megascolecoid earthworm genera (Oliza- chasta) of Australia, Part 1—Reclassification and checklist of the megascolecoid genera of the world. Prov. R. Soe. Od B2(6), 75-86. JAMizson. B. G. M,. (1973).—Earthworms (Megascolecidac: Oligochueta) from Mount Kosciusko, Australia. Rec. Ast. Mus. (in press.) . MICHAELSEN, W. (1907a).—-Oligochaeten von Aus- tralien. Abh. Geb. Naturw., Tamburg 19(1), 1-25. MICHAELSEN, W. (19076) —Oligochaeta in: Die Fauna Sidwest-Australieny 1(2), 177-232. SHANNON, J. H. (1920).—On the structure of 2 new species of carthworm from South Aus- tralia, Megascolex fletcheri. Proc, R. Soc. Viet. 32, 301-313, Pl. XXVII-XXXI AERIAL DISPERSAL OF ADULT CARDIASPINA DENSITEXTA (HOMOPTERA:PSYLLIDAE) IN SOUTH AUSTRALIA BY T. C. R. WHITE* Summary WHITE, T. C. R., 1973. Aerial Dispersal of Adult Cardiaspina densitexta (Homoptera:Psyllidae) in South Australia. Trans. R. Soc. S. Aust. 97 (1), 29-3 1, 28th February, 1973. Living adult C. densitexta were captured at 152 m and 305 m above the ground in the vicinity of Keith, South Australia during the spring. This finding supports the hypothesis that the adults of the spring generation generally function as the effective dispersive stage in the life cycle of this insect. AWRIAL DISPERSAL OF ADULT CARDIASPINA DENSITEXTA (HOMOP- TERA: PSYLLIDAE) IN SOUTH AUSTRALIA by T. C. R. WuiTeE* Summary Wurrr, T. C. RK. 1973, Aerial Dispersal of Adult Cardiaspina densitexta (Homaptera: Psyllidac) in South Australia. Trans. R. Sac. §. Aust. 97 (1), 29-31, 28th Febrmary_ 1973. Living adult C. densitexta were captured at 152 m and 305 m ahove the ground in the vicinity of Keith, South Australia during the spring. This finding supports the hypothesis that the adults of the spring generation generally function as the effective dispersive stage in the life cycle of this insect. Introduction Clark (1962) concluded as a result of his obseryations and experiments with adults of Cardiaspina albitextura Taylor that emerged in the autumn, that they tend not to disperse far from their point of origin, and that there- fore this is “ . not a strongly dispersing insect.” Studies of the closely related Cardiaspina dénsitexta Taylor (White 1970a) suggested that although this seemed to he true of the generation of adult C. densitexta that emerged in the summer and autumn, it did not seem to be true of the generation that emerged in the spring. During summer and autumn, trees that were isolated from the established infestations were rarely colonized, Also at this time of the year. adulis seemed to show great “reluctance” to leave the foliage on which they had devel- oped, On the contrary, during spring it was commonplace for isolated trees to be colonized quickly. Also direct observation of the be- haviour of adults at this season of the year showed that they had a strong tendency to fly up and away from the foilage on which they had lived as nymphs. These observations led to the hypothesis that C. densifexta exhibits two types of seasonal behaviour: (1) non-dispersive, serving to con- Sentrate summer and autumn adults—and sub- sequent egg-laying—on favourable foilage; (2) dispersive, serving to distribute the adults emerging in ihe spring away from depleted foilage ind increasing the chance of some of them finding fresh foilage. This would suggest that the adults thai emerged in the spring were the effective dis- persive stage in the life cycle of C. denvirexta, most probably in the manner proposed by Lewis & Taylor (1965). Their analysis of many aerial samples demonstrated that “high altitude and long distance migration is very highly correlated with flight by day and small size.” Such an hypothesis presupposes that adults of C. densitexta which emerged in the spring were present high in the air where they would be widely and randomly dispersed by air cur- rents and winds. In 1964 an attempt to demon- strate this was unsuccessful. By the time a suitable technique had been developed, num- bers of C. densitexia had fallen to very low levels, reducing to near zero the probability of catching the few individuals that might have been present in the aerial plankton, This paper Treports a second attempt to catch airborne adult C. densitexta at a time when they were abundant. Materials and Methods Nets mounted on a steel ring 38 cm in diameter were towed from the wing of a Cessna 172 aeroplane flying at 1352 and 305 m above the ground. Details of the construction * Department of Zoology, University of Adelaide, Adelaide, S. Aust. 5000. Present Address; School of Natural Resources, University of the South Pacific, Sova, Fiji, 30 TCR, of the nets and the cing, and of the method of Operaling, were described previously (White 1970b). All samples were of 15 minutes duration. Euch net was released when the aeroplane had levelled off at the required height and was cruising at 121-131 km/h. Height and speed were maintained as accurately as possible for the duration of each sample. All nets were kept sealed in plastic bags until immediately before being used, At the completion of each sample a knot wus tied in the net before it was detached from the ring and resealed in w plasti¢ bag. All bags were returned to the laboratory before being opened and the nets immersed in 70% alcoho! before the knots were untied. All collections were made over a relatively amall area between Keith and Willalooka jin the southeast of South Australia (White 1970b, fig. 2), At the time the host plants (Eucalyp- ius fascieulosian Fv.M.) in this locality were carrying w moderate to high population of C. densitexta, wind ahout 50%. of the adults had emerged. Results Forty-one samples {Table 1) were collected during, five days, thirty at 152 m and eleven at 305 m, Twenty cight contained adult C. den- xitexia, the catch varying from one to nine per sample at 152 m, and one to five per sample at 305 m, A total of 60 adults were caught. there being approximately equal num- hers of males and females, Several were ob- served crawling around in the nets after these had been placed in ptastic hags. TABLE | The number of adult C_ densitexta captured No. of Aln- Date Samples — tude a 9 + Fatal Lexi7t LL(7j* [52m 5 5 1 oul 2.x1.71 77) 1S2m fi 8 2 16 3x17] §(3) 132m 2 2 1 3 VL .xi.7t 4(3) [52m 4 5 2. al 4(4) wim — 2 ] 3a 12.xi.71 73) 305 m 5 of 3. 614 Total 41(28) _— 22 28 #10 60 * Number of samples containg C. denstrexta in parenthesis. + Damuged individuals lacking an abdomen, A net with a diameter of 38 cm, pulled through the air at a mean speed of 126 km/h, would sift 221 m* of air per minute—3319 m! in a 15 minute sample. But because of the WHITE. “cushion” of air formed in Front of the net. at ix improbable that this volume of air would have passed through the net, Much of it would have been deflected around the sides of the net, No attempt was made to assess the “effective” diameter of the nets—it. may well have been no more than 2.5 om to 5 ¢m but if a conser- vative 7.5 em miurgin is deducted to whow for deflection an clfevtive diameter of 23 ¢m re- mains. Then 1188 m® of air would have been sampled in 15 minutes. A 152 m high block of air ubove a hectare of jand contains 1,520,000 m* of air, at 305 m, 3,050,000 m*, Tf the adult psyllids were distributed wt random through this air, the sampling indicated densities of from about 1,300 to 11,500 per hectare to a height of 152 m and trom 2,500 to 12,800 per hectare to 305 m. Discussion and Conclusion The number of unknowns makes any uttampt to quantify the density of adult psyllids in the aerial plankton unrealistic. Quite apart trom the problem of the effective size of the sampling unit, it is likely that the distribution of ait-borne psvilids was far from random. The time of day, ambient temperature, wind speed and the extent and duration of the warm au “thermals” rising from the ground would all have contributed to a patehy and variable distribution, both vertically and horizontally, Almost certainly this sampling underesti- mated the number of these insects in the air over any area of land, But equally certainly it demonstrated that there were very many of them carried to considerable heights above the trees on which they emerged; sufficient to ensure that they would have been scattered over many square km of land, As the air cooled each evening and they returned to earth. relutively few of them would have been for- junate enough to Jand on a suitable host plant. But the few that did would have survived, and, with their huge capacity for increase. soon utilized the available food. The evidence from this sampling. combined with that previously reported {White 1970a), demonsteated that the adults of C. densitexta that emerge in the spring are the means by which this species of psyllid i widely and effectively dispersed. Other records of adult psyllids captured high in the air (Glick 1961; Freeman 1945, Hardy AERIAL DISPERSAL OF CARDIASPINA DENSITEXTA 31 & Milne 1938) and as far as 298 km from the nearest land (Yoshimoto & Gressitt 1963; Harrell & Yoshimoto 1964) suggest that this method of dispersal is common within the Psyllidae. Acknowledgements A grant from the Endowment and Scientific Research Fund of the Royal Society of South Australia made it possible for this sampling to be carried out. I am grateful to Gordon Burnard for arranging the hire of the aeroplane from the Pinnaroo Aero Club and for his and Barry Browne’s patient and skillful piloting. To Joan Burnard my thanks for her hospitality and for allowing her kitchen to be converted into a temporary laboratory, References CLaRK, L. R. (1962).—The general biology of Cardiaspina_ albitextura (Psyllidae) and its abundance in relation to weather and para- sitism. Aust. J. Zool. 10, 537-86. FREEMAN, J, A. (1945).—Studies in the distribu- tion of insects by aerial currents, The insect populations of the air from ground level to 300 ft. J. Anim. Ecol, 14, 128-54. Guicx, P. A. (1961).—Airborne movement of the Pink Bollworm and other arthropods. Tech, Bull. U.S. Dept, Agric. 1255, 1-20. Harpy, A. C. & Ming, P. S. (1938).—Studies in ihe distribution of insects by aerial currents. Experiments in aerial tow-netting from kites. J, Anim. Ecol. 7, 199-229, Harrei, J. C. & Yosuimoto, C. M. (1964).— Trapping of airborne insects on ships on the Pacific, part 5. Pacific Insects 6, 274-282. Lewis, T. & Taytor, L. R. (1965).—Diurnal periodicity of flight by insects. Trans. R. ent. Soc, Lond, 116, 393-479. Waite, T. C. R. (1970a).—Some aspects of the life history, host selection, dispersal and oviposition of adult Cardiaspina densitexta Comaninrs = Feyiligar). Aust J. Zool. 18, 105-17, Waite, T. C. R. (1970b).—Airborne arthropods collected in South Australia with a drogue- net towed by a light aircraft. Pacific Insects 12, 251-259. Yosutmoto, C. M. & Gressirr, J. L, (1963).— Trapping airborne insects in the Pacific- Antarctic area, 2. Pacific Insects 5, 873-883. LIFE HISTORY, LARVAL MORPHOLOGY AND RELATIONSHIPS OF AUSTRALIAN LEPTODACTYLID FROGS BY G. F. WATSON AND A. A. MARTIN®* Summary WATSON, G. F. and MARTIN, A. A., 1973. Life History, Larval Morphology and Relationships of Australian Leptodactylid Frogs. Trans. R. Soc. S. Aust., 97 (1), 33-45, 28th February, 1973. Disagreement exists regarding the phylogeny, relationships and classification of Australian leptodactylid frogs. Analysis of their life history patterns indicates that one of the present two subfamilies, the Myobatrachinae, is a close-knit natural group, whereas the other, the Cycloraninae, is more heterogeneous. In particular, the genus Cyclorana does not conform with the cycloranines, and in terms of life history has strong affinities with the Hylidae. No close relationship between the Myobatrachinae and the Cycloraninae is evident from life history data. LIFE HISTORY, LARVAL MORPHOLOGY AND RELATIONSHIPS OF AUSTRALIAN LEPTODACTYLID FROGS by G. F. WatTson* and A. A, MartTIn* Summary Wwarsan, G, PF, and Martin, A. A., 1973. Life History, Larval Morphology and Relationships of Australian Leptodactylid Frogs. Trans, R. Soc. S. Aust., 97 (1), 33-45, 28th February, 1973, Disagreement exists regarding the phylogeny, relationships and classification of Australian leptodactylid frogs. Analysis of their life history patterns indicates that one of the present two subfamilies, the Myobatrachinae, is a close-knit natural group, whereas the other, the Cycloraninae, is more heterogeneous. In particular, the genus Cyclorana does not conform with the cycloranines, and in terms of life history has strong affinities with the Hylidae. No close relationship between the Myobatrachinae and the Cycloraninae is evident from life history data. Intreduction In the first substantial monographic study of Australian anurans, Parker (1940) divided the Australian representatives of the family Lepto- dactylidae into two subfamilies: Cycloraninae and Myobatrachinae. The major characters used to define the twa groups were the struc- ture of the tongue, hyoid apparatus, larynx and thigh musculature, Martin (19672) noted that biological characteristics, particularly life history, were broadly consistent with Parker’s division, Lynch (1971), using a complex of morphological, osteological and ecological characters, substantiated Parker's taxonomic interpretation; he further divided Puarker’s Cycloraninae into two tribes, Cycloranini and Limnodynastini. Tyler (1972a) investigated the superficial mandibular musculature and vocal suc struciure of Australian leptodacty- lids, and came to conclusions similar to those of Parker and Lynch, with one important ex- ception, Tyler found that Cyclorana Stein- dachner did not conform with either the Cycloraninae or the Myobatrachinae; and he questioned its familial disposition, noting that it shared some characters with the amily Hylidae. The generic classification of Australian Jeptodactylids has undergone considerable modification since Parker's work. Heleioporus, as recognized by Parker, was divided into two genera, [eleioporus Gray and Neobarrachur Peters. by Main (1957a); and the new genera Kyarranus Moore, 1958 and Taudactylus Stranghan & Lee, 1966 have been erected. Tyler (1972b) removed Crinia darlingtoni to # new genus, Assa. Blake (in press), using a polythetic mumerical approach; finds that Crinia is divisible into three gencta, and group- ings corresponding to these genera are used here, They are referred to as the Crinia has- well’ group (including C. haswelli and C. georgiana); the Crinia laevis group (including C, Jaevis, C. leai, C. lutea, C. rosea and C. victoriana); and the Crinia signifera group (in- eluding all other species of Crinia). Blake (in press) also finds that Mezacrinia Parker does not warrant separation from Pseudophryne Fitzinger and he intends to synonymise these two genera; hence they are not treated separ- ately here. The current composition of the Australian leptodactylids is shown in Table 1. The present contribution summarizes the available data on the life histories and larval morphology of Australian leptodactylids. Such information is useful from two points of view, First, life history stages provide morphological characters independent of those exhibited by + Department of Zoology, University of Melbourme, Parkville. Vic. 3052. a4 G. F. WATSON and A, A, MARTIN adults, and can therefore be uscd to test phylogenetic relationships based on studics of adults (such gs the suggested hylid affinitics of Cyclorana), provided that care is taken to recognize convergence (Inger 1958; Griffiths 1963}. Second, life history is an indicator of geferal adaptive ecology, and generic defini- tion is currently based on ecological as well as morphological characters (Mayr 1969). Inger (1958) has demonstrated the utility of life history data in anuran classification at the im- frafamilial levels, and this approach was used by Martin & Watson (1971) in an analysis. of the family Hylidae. Although Lynch (1971) took life histories into account in his analysis of the leptodactylids, mast of his dats on Aus- trilian forms as derived from the literature, and is often inadequate or erroneous. TABLE | fnfrafamiltal classifications of Astralian leprodavtytids, Adelotun Kyarramis q Lechriodus Linney Lim nodynuntcs: fork 197) Subsamii " ft Philovin Cycloraninae Tribe | ; F Yas Meleigporus | Bates Subfamils Cyeloruninac (Tyler 19729) Mixophyer Tribe Neobatachut Cycloranini Notaden | cad 171) Cyclorans Crinia laevis group Crinia signitera group Glavertia Myobarrachus Peeudophryne Taudactylus Uperoleia Subfamily Myobatruvbinar (Varker 1940; Lyaet 197t, Asia Crinia haswelh sroup | f Teler 19720; Make in prose) Material and Methods Material representing all but four of the 17 venera of Australian leptodactylids has. been examined, The four gencra not studied are the cycloranine Noteden Gunther ahd the myobatrachines Awsa Tyler, (lanertia Loveridge and Myehatrachuy Schlegel. For these genera data have been drawn from the literature. One or more species of each of the other genera have been examined; all obser vations mot supported by 4 reference are original. In some cases (e.2, Limnoadynastes, the Cvrinia signifera group) enough species have been stucbed to be fairly confident that the limits of intrageneric vartalion in life his- tory have been detected; in others (¢,g. Tanda tylus), only one species hus been examined and the present account may therefore not be characteristic of the genus. Identity ul life history stages was established! hy rearing eges of known parentage, or by rais- ing to metamorphosis a portion of each tuilpele sample, The only exception is Taudacrylus, where identification of the larvae is based on the fact that they were collected at the type locality of 7. diurnus, and are distinct fram the larvae of any other anuran known to in- habit the area. Although data on numerous characters were assembled, five major feutures of the life history showed consistent variation and were employed in our analysis, These features, inost of which are illustrated in Martin (1965), are: (1) Type of egg mass: whether foamy or nat. (2) Larval development: whether terres- trial or aquatic. (3) External gills: whether present or ab- sent in embryonic development, Number of rows of teeth in the upper lubium of the larval mouth: whether nonc, two, or more than twa. Disposition of labial papillae in the larval mouth; whether completely sur- rounding the mouth disc (na gaps), or with an anterior gap, or with both .an- terior and posterior zaps. One additional character commonly em- ployed in larval descriptions—whether the anus is median or dextral—is included for the sake of complcteness, but in many groups 7 is too variable (even within genera) to be use- ful in the analysis of affinity (Lee 1967; Lynch 1971). The larval morphology of each genus is Wustrated by drawings of the indpoles of one or more species in lateral view, and of the larval mouth dises, Larvae between stages 3f) und 38 of Giosner (1960) were used for illu- stration. Where material was avilable For several species in a genus, the specics selected for illustration and description is generally one which has not been considered in our pre- vious publications (e.g. Martin 1965, 19674), The description relers to the species illustrated, and variations in other species are noted. Drawings were mude with the aid of a stereo- scopic microscope, using photographs, a cameta lucida, or an ocular micrometer and squared paper. (5) Survey of Life Histories Adelotus Ogilby Species examined: A. Arevis, Trani Mt_ Nebo. Old. The egg mass is foamy und is deposited In standing or flowing water, development 4s AUSTRALIAN LEPTODACTYLID FROGS Sie me, Cree ea epE ITS os, C Pepa a ee ey my S97 > pcean, SPER Fig. 1, Left lateral view of larvae of: A, Adelotus brevis; B, Lechriodus fletcheri; C, Kyarrunus sSphagnicolus; 45mm, aquatic. The eggs lack pigment and have a diameter of 1,7 mm (Martin 1967a). There are no external gills. The anus is dextral, and the larva has an unspecialized body form (Fig. 1A). There are three upper and. three lower rows of labial teeth (not two upper and three lower as stated by Lynch 1971), and a gap in the labial papillae along the anterior margin of the mouth disc (Fig. 2C), Adelotuy is a monotypic genus. Kyarranus Moore Species examined: K- sphagnicolus, from Point Lookout, N.S.W. The foamy egg mass is placed out of water, in damp sphagnum moss, and the larvae do not feed, though they may become free-swimming (J. M. de Bavay, pers. comm.). Small external gills are present, The larva has a relatively long tail and broad fin; the anus is median (Fig. 1C). The mouth parts are reduced, with well- developed jaws but no labial teeth; the papillary border is broken anteriorly (Fig. 2D). The life history of K. loveridgei is very similar (Moore 1961). BD, Limneodynastes interloris; E, Philoria frosti, In each case the bar represents Lechriodus Boulenger Species examined: L. flercher?, ftom Cunning- ham's Gap, Qld. Development is aquatic, often in highly ephemeral situations. The egg mass is foamy and the ovidiameter is about 1.7 mm (Martin 1967a). Long, filamentous external gills are present. The larvae (Fig, 1B) are carnivorous and development is rapid (Moore 1961), The anus is median. The mouth disc (Fig. 2A) has large jaws, and six upper and three lower rows of labial teeth. Labial papillae are absent from the anterior margin of the mouth disc. Lechriodus is incorrectly described by Lynch (1971) as having only two upper labial tooth rows, L. flercheri is the only representative of the genus in Australia, but there are several species in New Guinea (Parker 1940). Limnodynastes Fitzinger Species examined: L. dumerili, L. fletcheri, L interioris, L. peroni, L. salmini, L. tas- maniensis, L. lerraereginae. 36 G. F. WATSON and A. A. MARTIN i . Panis we ~™ psy ree ‘ust tle eV, we Er alee ge Oh veel apnea aytyner en ee eee a eg com a UA ~ ah mM rt ‘aye " ven eH Ye nny r to a x 1 ee Nara wh a we bingy SILAS VERA VEY ITER S PIAVIL ERAN —oe My yi ca % MT Nanya NTE e Fig. 2. Laryal mouth discs of: 4, Lechriodus flétcheri: B, Limnodynastes interioris; C, Adelotus brevis; D, Kyarranus sphagnicelus; FE, Philoria frasti. In each case the bar represents 1 mm, Species deseribed: L. inrerioris, from Boree Creek, N.S.W. The egg mass is large and frothy, and is deposited in water among vegetation, under logs or rocks, or in water-filled burrows in stream banks (Martin 1967a); development is aquatic. The ovidiameter is about 1,7 mm. Externat gills are small and unbranched. ‘The larva (Fig. 1D) has a generalized body form; the anus is median, There are six upper and three lower rows of labial teeth, and Jabial papillae suzround the mouth disc except for the anterior margin (Fig, 2B). This life history pattern seems fairly con- stant throughout the genus. In southern Vic- torign and Tasmanian L. peroni, the eggs are unpigmented (Littlejohn 1963a). Egg counts range from 1,100 in ZL. tasmaniensis to 3,900 in L. dumerifi (Martin 1967a), All species have at least 4, und usually S—6, rows of teeth in the upper labium. Philoria Spencer Species cxamined: P, frosti, from Mt, Baw Baw, Vic. AUSTRALIAN LEPTOGDACTYLID FROGS 37 ET gl, fig SH Fig. 3. Left Jateral view of larvae of: A, Heleioporus australiacus; B, Cyclorana cultripes; C, Mixe- phyes balhus; D, Neobatrachus pictus, Tn each case the bar represents 5 mm. The frothy egg mass is placed in damp sphagnum near water; the eggs are unpig- mented and have a diameter of 3.9 mm (Liftle- john 19636). Small external gills are present. The Jarvae may be free-swimming but apparently do not feed, The anus is median and the tail fin large in proportion to the body (Fig. 1B). The mouth has well-developed jaws, and papillae on the Jateral and posterior margins of the disc, but labial tecth are absent (Fig. 2B). Philoria is a monotypic genus. Heleiaporus Gray Species examined: H. awstraliacus, ftom 12 km 'S. of Walhalla, Vie. The eggs are unpigmented and measure 2.6 mm in diameter; egg counts of four masses ranged from 775—1,239 eggs. The egg mass is foamy and is deposited in standing or flowing water concealed in vegetation or in burrows; development is aquatic. The external gills are prominent. The Jarvae (Fig. 3A) are un- specialized, with a median anus. The mouth disc has six upper and three lower rows of {ahial teeth, and an anterior gap in the papil- lary border (Fig. 4A). lee (1967) has described the lite histories of the five Western Australian species of Heleivporus. In these, the cggs (mean ovi- diameters 2.6—3,8 mm; mean egg counts 160— 480 eggs) are laid in dry burrows which are later flooded, and the larvae undergo aquatic development. The anus muy be median of dextral. and there are 5-6 rows of teeth in the upper Jabium- Mixophyes Gunther Species examined; M. halbus, M. fasciolatus. Species described: AM]. balbus, from Point Look- out, N.S.W. The cggs (ovidiameter about 2.8 mm) ure pigmented and are laid in clusters on rocks or gtavel near the edge of flowing streams, Each egg has a distinct separate capsule, and the mass 3s not frothy, External gills are present. Development is aquatic, and the larva is a large and powerful lotic form (Fig, 3C). The anus is dextral. The mouth disc has a com- plete papillary border, and six upper and three lower tows of jabial teeth, There are also 5-6 lateral rows on each side near the angle of the jaw (Fig. 4B). The hind limbs develop in a membrgnous sac and are not visible until late in development. The life histories of Mf. balhus and M- fasciolatus appear to be essentially identical (Martin 19674). Details of life history in the other two members of the genus are not recorded, Neobatrachnus Peters Species examined; N. centralis, N. pictus. Species described: N. pictus, from Savernake, N.S.W. The eggs are pigmented and about 2.2. mm in diameter. They are Jaid in strings of jelly wound among submerged vegetation in stand- ing water, and development is aquatic. Small external gills are present. The larvae are active swimmers with relatively plump bodies.and short § G, F. WATSON —_——> 7 SSP mht ee Teac ee Cr < nm al Arnaut sen aie POLLEN sry naan nen oo Ae and A, A. MARTIN Seti, n Uh Sener a, yltss f iL atl ek RA Usyas 14-4 Peery yan? a, acl ; re ST 4 ee a gabtirae ing Fig. 4. Larval mouth discs of: A, Heleioporus ausiraliucus; B, Mixophyes halbus; C, Neobatrachts pictus; D, Cyclorana coltripes. In each case the bat represents 1 mm. jails (Fig. 3D). The anus is median or slightly displaced to the right. Papillae are absent from the anterior margin of the mouth dise, and there ate three rows of teeth in each labium (Fig. 4C). The jaws are very robust, presum- ably reflecting the fact that the larvae feed by ingesting large fragments of plant and insect material (M. J. Tyler, pers. comm.). In castern populations of N. centralixs the eygs huve discrete capsules and are laid sep- arately or in loosely adherent clumps. The three endemic Western Australian species lay their eggs in Jong strings (Main 1965, 1968). Notaden Gunther Species deseribed: N. richollsi, from Munka- yarra, W.Aust. This account is taken from SJater & Main (1963). The eggs are 1,3 mm in diameter and pigmented; they are laid in temporary pools and development is aquatic. The form of the egy mass, and whether or not external gills develop, are not recorded. The anus is median. There ate three upper and three lower rows of labial teeth, and papillae extend around the sides and back of the mouth disc. Vhere is no information on record concern- ing the life history of the other members of this genus, N. hennetti and N. melanoscaphus. Cyclorana Steindachner Species examined: C. australis; C, cultripes, C, platycephalis. Species described: C, Creek, N.T. Development is aquatic, "The eggs are small and pigmented and are Jaid in clusters, without distinct separate capsules, in water (Main 3965), Embryonic development is not re- corded, The larva (Fig. 3B) has a distinctive acuminate tail tip; the anus is dextral, though often only slightly displaced from the midline. There are two upper and three lower tows of labial teeth, and papillae occur along the lateral and posterior margins of the mouth disc (Fig. 4D). The eggs and larvae of C, platyeephalus, and the larvae of C. australis, are. similar to those of C, cultripes. No data are availible for other species in the genus. culrripes, from Pine AUSTRALIAN LEPTODACTYLID FROGS wy a eer Fig. 5. Left lateral view of larvae of: 4, Crinia kaswelli; 2, Psendophryne corrobaree: C, Crinia leeviy: DBD, Crinia rasea. In each case the bar represents 5 mm. Assa Tyler Species described: A. darlingtoni, ‘rom the Macpherson Range. Qld. The eggs are unpigmented and average 2.5 mm in diametet. Oviposition and embryonic development are not recorded. The larvae de- Velop in a brood pouch of the male, but details of their morphology have nor been described (Straughan & Main 1966). The genus A'vsa is monotypic. Crinia Tschudi ‘CRINIA HASWELLI group Species examined: C. Aaswelfi, from 7 km W. of Orbost, Vic, The eggs measure about 2 mm in diameter uid are pigmented, with distinct individual capsules. They are laid in water and develop- ment js aquatic. External gills are absent. The larva (Fig. 5A) is a specialized nektonic form with high fins. The aous is dextral. The tadpole appeurs to feed largely on plankton, The mouth has two upper and two lower rows of labial teeth, and a single row of papillae bor- dering its lateral and posterior margins (Fig. 6A). The Western Australian C. georgiana, the only other member of this group, has 4 markedly different pattern of development (Main 1957b, 1965). The eggs ate latd in permanent streams and soaks. Larvae are of the lotic type, being flattened, and with long, slender tails (see Main 1957b, Fig. 2a). There are three rows of teeth in egch labium, and the papillary border has both anterior and posterior gaps. CRINIA LAEVIS group Species examined: C. laevis, C. resea, C. vie- 7oriand, Species described; C. lJaeviy, from Wynard, Tas, and C, resea, from Pemberton, W.A, In C. leevis the eggs are pigmented, about 3 mm in diameter, and with discrete capsules- They are laid in concealed sites on Jand. and embryonic development is intracapsular. There are no external gills. After the eges ure flooded by winter rains the larvae (Fig. 5C) hatch and undergo aquatic development. The anus is dextral, The mouth has two upper and three lower labial tooth rows, and papillae are absent from the unterior and posterior margins of the mouth dist (Fig. 6C). Tn C, rosea the eggs are unpigmented and have a diameter of 235 mm (Main 1957b), The entire development takes place on Jand, and the larva (Fig. 5D) is highly modified, with no mouth disc (the mouth is a simple slit), a large yolk sy¢ and an elongate tail, The anus. is. median, All members of this species group have one or other of these modes of development: the C. Inevis pattern is shared by C. leai and C. victoriana, and the C. rosea pattern by C’. lutea (Litlejohn & Martin 1964; Main 1957b, 1963). CRINIA SIGNIFERA proup Species examined: C. parinsignifera, C. riparia, C. signifera, C. sloanei, C.. tasmaniensix, Species described: C. parinsignifera, from 6 km §.E. of Wandong. Vic. The eggs are 1.3 mm in diameter, pig- mented, and with distinct individual capsules. 40 G. F. WATSON and A. A. MARTIN é 1) Z os weer ele 73 2 7s re pal o in to EY Nui ity “hh v Se Twa a ut ~ wy Sai i Ag * - # nN aa h. wun coo tr wl a0 ~ wo ee ec ass } petra ‘Ry Mig oj uy vein in rl fo ANANTH Ming Nu Won NAO Dr. Aa Ty : o Se ange ve) Ss ne Rowny oN S Od " eo a) } A c . ~—S a SS Pb ‘ m “ai 4 S ay i me > yp Ln Se 1 yu yr Fig. 6. Larval mouth discs of: A, Crinia haswelli; B, Pseudophryne cerroberce: C, Crinia laevis; D. Crinia parinsignifera; E, Taudactylus diurnus; F, Uperoleia marmorata, In euch case the bar represents 1 mm, AUSTRALIAN LEPTODACTYLID FROGS 4i Ovipasition und developmient are aquatic, Ex- ternal gills are absent. The Jarva (Fig. 7A) is unmodified, with a dextral anus. The mouth has an incomplete papillary border, with both anierior and posterior gaps, and there are two upper and three lower tows of labial teeth (Fig. 6D). There is little variation in life history in this group. The same basic pattern is shared by C. glauerti, C. ingsignifera, C. pseudinsignifera; C. svbinsignifera and C. tinnula (Main 1957b, 1965; Straughan & Main 1966). In C. fas- maniensis and C. riparia the eggs are larger (ovidiameters 1,96 and 2.27 mm _ respec- tively), and the latter has terrestrial. oviposition und a lotic type of larva (Martin 1967b; Little- john & Martin 1965). Glauertia J overidge Species described: G. russelli, from Western Australia. The cggs have a diameter of about 1.4 mm atd are laid in water: development is aquatic (Main 1968). No other details of the life his- tory have been recorded, and the life history of G_ miohergt is entirely unknown. Myobatrachus Schlegel Species described: M. gouldi, from Western Australia. The cggs reach a diameter of 5,5 mm (Wat- son & Saunders 1959). No other life history data are on record. but. from the large egg size and general adult ecology it is very probable that development takes place on land (Main 1968). Myobatrachus is a monotypic genus. Pseudophryne Fitzinger Species examined: P. australis, P. bibreni, P. curiacea, P. correbayee, P. dendyi, P, remimarmorata. Species described; P. carreboree, from Mt. Ginini, A.C.T, The eggs are pigmented and have a diameter of about 3 tum. They haye firm, discrete capsules and are laid on land, in tunnels in sphagnum. Embryonic development occurs within the capsule and there are no external gills. The larvae (Fig. 5B) develop in water. The anus is dextral and the mouth has two upper and three lower rows of Jabial teeth. There are gaps in the papillary border at both the front and reat margins of the mouth dise (Fig. 6B). This pattern of life history—large eggs laid on land, intracapsular embryonic development, and aquatic lurval development—is consistent throughout the genus (Martin 1965, 19674), with the exception of the Western Australian P, douglasi, in which oviposition is aquatic (Main 1964), Blake's (in press) revision of the myobatrachines includes Meracrinia nichellsi in Psendophryne, but nothing is known of its life history (Main 1968), Taudactylus Straughan & Lee Species cxamined: 7. diurnus, from ML. Giotious, Qld. Ovarian eggs reach 2,2 mm in diameter, but oviposition and embryonic deyelopment are not recorded (Straughan & Lee 1966). We found larvae (Fig. 7B) in a slow-flowing ercek. The anus is dextral. The mouth structure (Fig. 6E) is unusual. The jaws are weakly developed and there are no labial teeth; but the disc is greatly expanded and umbrells-like, with a complete papillary border. The life history of ZT. aeutirostris is not recorded, and therefore whether or not this unique Jarval form is typical of the genus is unknown, n wa phdh =) Dagan meal Fig, 7. Left lateral view of larvae of: 4. Criniz parinsignifera; B, Taudactylus diurnus; C, Uperoleia marmorata, In each case the bar represents 5 mm, 42 G. Uperoleia Gray Species examined: U, marmoratd, U. rugosa. Species described: U/. marmorata, from 38 km N. of Bateman’s Bay, N.S.W. The eggs are pigmented and have discreté capsules; the ovidiameter is about 1.5 mm. Development is aquatic, External gills do not develop. The larva is unspecialized (Fig, 7C); the anus is dextral. The mouth (Fig. 6F) has F. WATSON and A, A. MARTIN two upper and three lower rows of labial teeth, and gaps in the papillary border at both front and rear. Moore (1961) incorrectly states that the papillae extend around the posterior mar- gin of the mouth disc; and both Moore (1961) and Lynch (1971) erroneously record that there is only one upper labial tooth row. The life history of 0. rugesa is very similar. Life history characters are summarized in Table 2. TABLE 2 Life history characteristics of Australian leptodacrylid genera Unoper Labia! Gaps in Labial Egg Mass Development FEatretnal Gills Tooth Rows Papillac bal Genus Species 3 Z é = & & 38 Genus Species z= & = 3 Fa E a “4 € = = a 7 ta w @ = + foe a = g EN a 5 0 z 2 i=] P< Begs e zg #4 FF = & > Z << <¢%e ANELOTUS a ee a=, & ae LHCHRIODUS + j= -«— oo —-— — + a» JF c= LIMNODYNASTES ce => r= ~ > —— Le os | — t — KYARRANLS + = — a ca — + — — + — PHILORIA ‘ao oe f Eo ie HELELOPORUS al Ses + = —> ~~ + —F 3 f MIXOPHYES — + tS fd om @& = 3 «he NEOBATRACHUS — _ + = = = = = as = = NOTADEN — & ‘tp 2 ~s =& 4 = == CYCLORANA — -b + — 2 — + — —, 7 — ASSA - ? — y 5 - CRINIA veoreiana — oo + = 2 = — 77 — le, +: haswelli — = = = & = 4- = = 4 =_— faeyis — = t. — — a — + >. — + itenif = + = + — => _ — No papillae slenifera sroup — + — — — = GLAUERTIA a” oe ; = -7 i. = pea MYOBATRACHUS 2 fen > + > PSEUDOPHRYNE ~ + 4 a = = = + — — Ea + TAUDACTYLUS ? oat > nS] = 2 SE UPEROLEIA >» te br a ae ia | i TS Sion —& 23 Discussion (i) Status of tHe subfamilies Life history data support the division of the Australian leptodactylids into the two sub- families currently recognized. The Myobat- rachinae are a close-knit, natural group of genera sharing several life history features, These are: eggs with discrete cupsules, ege masses not foamv; no external gills; « dextral anus; two upper and three lower rows of labial ieeth; and anterior and posterior gaps in the papillary border. The few exceptions are species of Assa, Crinia and Taudactylus whose larvae are modified for development in a parental pouch, or in other specialized niches. The Cycloraninae are a more heterogeneous assemblage. Leaving aside C}clorana (which is discussed. below), there is still a variety of #Th brood pouch of male developmental patterns und larval forms in this group. The frothy egg mass has apparently evolved at least twice, in view of the occur- ence of two different methods of foam produc- tion, In Adelotus, Kyarranus, Lechriodus, Lim- nodynastes and Philoria the foam is formed by the female “paddling” with her forelimbs, which have specialized flanges on one or more fingers, during amplexus. This paddling causes a stream of bubbles to pass backward beneath her body and become entrapped in the mucus which accompanies extrusion of the eggs (Mar- tin 1967a). Heleioporuys females Jack these flanges, and in this genus the foam is. presum- ably produced by a different (but presently unknown) method (Martin 1970). Again ex- cluding Cyclorana, life history features com- mon to most cycloranines are: eggs with dis- crete capsules, sametimes in foamy masses! AUSTRALIAN LEPTODACTYLID FROGS 33 external gills present, 3-6 upper rows of labial tecth; and no posterior gap in the papillary border. The anus is usually median, but is often slighily offset tn Neebdarrachus, and fully dextral in Adeloms and Mixophyes, Lynch’s (1971) division of the Cycloran- inae into tribes is based on breeding biology and the position of the vomerine teeth. The Limnodynastini consists of the genera in which foamy egg masses are produced with the aid of the Hanged fingers of the female. This group is of course relatively homogeneous in terms of life history, since if was partly defined in this way. The Cycloranini, an the other hand, exhibit a variety of life history patterns, and from this point of view do not appear Lo con- stitute # natural group (ii) The bearing of life history data on generic delimitation The current generic delimitation of Austra- lian lJeptoductylids is broadly consistent with what is known of their life histories. In cases where genera haye very similar life histories, ea. Neobarrachis and Notaden, Pseudophryne and the Crinia laevis group, there is sufficient differentiation in adult morphology and ecolozy tO warrant generic separation, The retnoval of Crinia darlingtoni to Assa by Tyler (1972b) and the subdivision of the remainder of Crinig by Blake {in press) are supported by life his- lory evidence. The developmental bialogy of Assa is unique among Australian leptodacty- lids, and the Crinia laeviy and C. signifera groups ure also definable in terms of life his- tory. The two members of the C. haswellf group have rather different life history patterns, but both are distinct from those of the C€- laevis and ©, signifera groups, Kyarranus and Philoria are the only genera whose status seems questionable in the light of life history data, The similarity between theny in Most aspects of both adult and Jarval morphology and ecalogy has already heen commented on by Littlejohn (19636) and Braitstrom (1970), and the latter has indi- cated his intention to synonymise Kyurranus with Piiloria. Such u change is clearly sup- ported hy evidence From their life histones, (ili) The position of Cyclorana Tyler’s (1972a) contention that Cyclorane does net cunform with the currently accepted concept of the Cycloraninas, and has hylid affinities, is strongly supported by life history data. Indecd, If regarded solely in lenms of life history, Cvclorana coincides very clusely with the pattern typical of Australian bylids ( Martin & Watson 1971). Characters which it shares with them, and which are almost unique among Australian leptodactylids, are the indistinct egg capsules, the general body form of the tadpole (particularly the acuminate tajl}, and the presence of two upper tabial tooth rows combined with the occurrence of papillae along the posterior margin of the mouth dise. Data from other sources, ¢.g, karyotype and mating cull structure, ure needed hefore a final decision can be made; but for the present it shoukl be recognized that the subfamilial dis- position of Cyclorana and the definition of the Cycloraninae require revision. liv) Phylogeny ef the Australian lepioducty- lids The phylogenetic relationships of the Aus- tralian leptodactylids are disputed, Parker (1940) speculates that the myobatrachines may have been derived from ihe cycloranines: whereas Tyler (1972a) regards the myobat- rachines as the primitive, and the cycloranines as the denved, group. Lynch (1971) believes that the two groups are not closely related, aud that they represent independent descendants from a primitive leptodactyloid stock, Our data do not contribute significantly to resolution of this question. If Cyclorana is left out of consideration then there are three main distinguishing features in. the fe histories of the two subfarnilies. These are (1) the absence of external gills in the myobatrachines, and their presence in nearly all cycloranines; (2) the presence of two upper labial tooth rows in the myobatrachines, and of three or more in the cycloranines; and (3) the pap in the lower labial papillae of the myobatrachines. The latter two characters stiggest that the myobatrachines are the more primitive group, but not necessarily that the cycloranines were derived From them. The presence of only two upper labial tooth rows is common in many families of anurans, ¢,g, most hylids. bufunids and Neotropical leptodactylids (OQuellman 1970; Martin & Watson 1971; Lynch 1971), The papillary gap is also a bufonid character- istic. Thug Lynch's (1971) suggestion that the myobatrachines may be a relatively unmodi- fied derivative of the proto-bufonid stock (i.e, the leptodactyloid group which was ancestral to the bufonids) seems reasonable, Bufonids do, however, possess external gills, Life his- tory data do not assist in the |nterpretation al cycloranine phylogeny, In terms of life history characters alone the only conclusions iat can 44 G. F. WATSON and A. A, MARTIN Key to Genera of Australian Leptodactylid Laryae (excluding Glauertia, Myobatrachus) 1. Larvae in brood pouch of adult male - 1. Larvae not im brood pouch of adult Miytniadtardtiaeta: 2, Mouth without labial teeth or papillae... — — — 6. ee vtssa .. Crinia laevis group (part) 3 2. Mouth with labial teeth and/or papillae oj... ee ee Wa aA . Labial teeth present . 4, Larvae whpiemented; freesuittatoniath i in 2 gtrearits Mt. ‘Glorious # are, + Old. 4. Larvae unpigmented or lightly pigmented 5. Larvae in pools or damp sphagnum, pherson Range, Qld. 6. Papillac camptetély surrptinding mouth . 6. Papillary border incomplete .... me 7. Papillary border with an anterior gap 7. Papillary border with both anterior and posterior gaps . 8. Mouth with 2/2 labial tooth rows . 8. Mouth with moré than 2/2 labial tooth TOWS ccc ccecee ere cveeene Mh, 9, Mouth with 2/3 labial tooth rows! .....,. 9 Mouth with more than 2/3 labial tooth TOWS ooccce sescceescssuesiusvessesvvecnviveee Oedeomcoeece 10. Mouth with 3/3 labial tooth rows 2.000.006 ee ee ee 10, Mouth with 4-6/3 labial tooth rows _. . Anus dextral 12, Mouth with 3/3 labial tooth rows —.......-.0...-— ~~ 12. Mouth with 2/3 labial tooth rows? — Labial teeth absent — | occsesisicsrspteerern etree 1. Anus median or neat-median pred aide 4 6 Talay dliurnas Ris wrist pyTeronegs eel orice tetrocti tute HSE 10000 .. 5 5. Larvae in pools or damp sphagnum; Mt. Baw Baw, Vic, . ~~ or in Hepronipas in earth; gies Philoria Point / Lookout, NS.W,; Mac- ; Kyarranus pes ene Teorhrevrtenetritae! pied ite daeenkirenalaiiattrs Mixophyes Cyclorana 10 .. ~ Holeioporus Lechriodus Limnodynastes Es Adclotus .. Neobatrachus Notaden . Crinia georviana _. Pseudophryne Crinia laevis graup (part) Crinia signifera group Uperoleia 1 Tadpoles of nearly all Australian Hylidae whose larvae are known also key out in this category. > Tadpoles of Bufo marinuy also key out in this category. be drawn are that the cycloramnes afte a more specialized and less homogeneous group than the myobatrachines, and do not show any close affinities with them. The phylogenetic position of Cyclerana can- not yet be decided. In terms of life history: it shows greatest affinity with the hylids, less with the. myobatrachines, and virtually none with the cycloranines. It is conceivable that it rep- resents a relict of a primitive stock which was ancestral, to both leptodactylids and hylids. M. J. Tyler (pers. comm,) is currently cogaged in an snulysis of the affinities of Cyclorana, and until his work ts completed further specu- lation is not warranted. (v) Larval characters as an wid to diagnosis The larval morphology and biology of most genera of Australian leptodactylids are sufficiently distinctive to enuble generic diag- nosis to be made in terms of these characteris- tics; they form the basis of the following dicho- tomous key. Acknowledgements Much of the material used in this paper was collected during field studies supported by grants from the Nufiicld Foundation and the Australian Research Grants Committee (Grant No. 66/16172) to Dr. M.. J, Littlejohn, and by the University of Melbourne Research Alloca- tion to the Department of Zoology. For donating material of species not repre- sented in our collection we thank Mr. J. M, de Bavay, Dr. M. J. Littlejohn, Dr. B.S. Low and Mr. M. J. Tyler. Some of the illustrations were prepared by Miss L. M. Howard and Miss M. Leahy, Dr, M. J. Littlejohn and Mr. M. J, Tyler read and criticized the manuscript. AUSTRALIAN LEPTOBACTYLID FROGS 45 References Biaxs, A. J. D. (in press) —Taxonomy and re lationships of myobatrachine frogs {Lepto- dactylidae): a numerical approach. Aust. J: Zool. Bearrstrom, B. H, (1970).—Thermnal acclima- tion ia Australian amphibians, Camp. Bio- chem. Physiol. 35, 69-103, Dvueicman, W. E. (1970).—The hylid frogs of middle America. Univ. Kans, Mus, Nat. Hist, Monogr. (1), 1-753, Goster, K, L. (1960).—A simplified table for Staging anuran embryos and larvae’ with notes on identification, Herpetologica Li, 183-190. Grirerrns, I. (1963).—The phylogeny of the Salicntia. Biol. Rey. 38, 241-292. Inger. R. F, (1958).—Comments on the defini- tion of gencra. Fvolution 12, 370-384. Lee, A. K. (1967).—Stodies in Australian Am- phibia Il. Taxonomy,, ecology, and evolution of the venus Heleioporus Gray tAnura: Leptodsctyhdae), Awsf J. Zool. 15, 367-439, LirtesoHn, M. J. (1963a).—Frogs of the Mel- bourne ared. Vier. Nat. 79, 296-304. Lerornionn, M. J, (1963b)—The breeding biol- ogy of the Baw Baw Frog Philaria fresti Spencer, Proc. Linn. Soc. N.S.W, &8, 2735— 276. LivTLeioun, M. J. & Martin, A. A. (1964),— The Crinia laevis complex (Anura: Lepto- ductylidae) in south-eastern Australia. 4 sss¢, J. Zool. 12, 70-83. LirrLesoan, M, J. & Martin, A. A. (1965).—A new species of Crinia (Anura; Leptodacty- lidae) from South Australia. Cupeia 1965, 319-324, Lyncu, J. D. (197)).—Evolutionary relationships. osteology, and zoogcography of Jeptodactyloid frogs. Univ, Kans. Mus. Nat. Flisi.. Mise, Publ, (53). 1-238. Main, A. R. (19574)—A new burrowing frog from Western Australia, WY Aust, Nat 6, 23-24, Main, A, R. (1957b),—Studies in Australian Am- phibia 1. The genus Crinia Tschudi it sowth- western Australia and some species from south-eastern Australia, Aust. J. Zool, 5, 30-55, Main, A, R, (1963).—A new species of Crinia from National Park, Nornalup. W. Arst. Nat. 8, 143-144. Main, A. R. (1964)—A new species of Pseudo- phryne (Anura: Leptadactylidae) fromy narth- western Australia. 4’. Amst. Nat. 9, G6-72. Main, A. R. (1965).—“Frogs of Southern Western Australia". (Western Australian Naturalists’ Club: Perth). Marr. A, R. (1968).—Ecology, systematics and evolution of Australian frogs. dey. Ecoi. Res, 5, 37-86, Martin, A. A. (1965)—Tadpoles of the Mel- borrne area. Vict, Nat. $2, 139-149, Martin, A. A. (1967a).—Australian anuran Iife histories: some evolutionary and ecological aspects. Jn: A. H, Weatherley, “Australian In- land Waters and Their Fauna; (Australian National University Press: Canberra.) Martin. A, A. (1967b).—The early development of Tasmania's endemic Anura, with com ments on their relationships, Proc. Linn. Soc. NUS. 92, 107-116, Martin, A. A. (1970)—Parallel evolution in the udaptive ecology of Jeptodactylid frogs of South America and Australia. Evolution 24, 643-644. Martin, A, A. & Warson, G. F. (1971)—Life history as an aid to generic delimitation in the family Hylidae. Copeia 1971, 78-89. Mayr, £. (1969).—*"Principles. of Syslematic Zoology.” (McGraw-Hill: New York.) Moorr, J, A. (1958).—A new genus. and spécies of Jeptodactylid frog from Australia. Amer, Muy, Navit. (1919), 1-7. Moorr, J. A. (1961),—The frogs of eastern New South Wales. Hull. Amer. Mus. Nut. Hiss. 121, 145-386, Parker, H. W. (1940)—The Australasian frogs of the family Leptodactylidae. Novit Zool. 42, 1-106. SLATER, P. & Main, A. R. (1963).—Nolés on the biology of Notaden nichollsi Parker (Amira: Leptodactylidac). W. Aust, Nat, $, 163-166. SrrRaucuan, J. R,, & Lee, A. K. (1966) —A new genus and species of Jeptadactylid frog from Queensland. Proc. R. Soc, Qd 77, 63-66, Plate TV. Straucuan, LR, & Mam, A. R. (1966).—Specig- tion and polymorphism in the genus Crinia Tschudi (Anura, Leptodactylidac) in Queens ine. Prov. R. Soc, Od 78, 11-28, Plates YI. Tyver, M_ J, (1972a).—Superficial mandibular musculature, vocal sacs and the phylogeny of Australo-Papuan Jeptodactylid frogs. Rec. S. Ast. Mus. 16, 1-20, Tyrer. M. 7. (1972b).—A new genus for the Australian leptodactylid frog Crinia darling- toni, Zool, Meded., Leiden 47, 193-201, Watson, J. A, L. & Sausmers, L. M. (1959).— Observations on the reprodutlive system ot the female of Myobatrachus gouldii (Gray), W. Aust. Nat, 7, 1-6. STUDIES ON THE ECOLOGY OF THE AGAMID LIZARD AMPHIBOLURUS MACULOSUS (MITCHELL) BY F. J. MITCHELL* Summary MITCHELL, F. J., 1973. Studies on the Ecology of the Agamid Lizard Amphibolurus maculosus (Mitchell). Trans. R. Soc. S. Aust., 97 (1) , 47-76, 28th February, 1973. Amphibolurus maculosus (Mitchell), the Lake Eyre Dragon, is restricted to arid salinas in the northern part of South Australia. The lizards live near the margins of the salinas where a suitable burrow area of fine, wind-blown sand underlies the buckled salt crust. Their essential refuge from the harsh environment is in the permanently damp sediments, which occur below these dry aeolian deposits underlying the salt crust. Preliminary laboratory experiments suggest that this lizard has a high temperature tolerance (CTM 48.9°C) and low evaporative water losses (1.1 mg/g/hr at 37.5°C) The harvest ant, Melophorus sp., which occurs in the same habitat, is an important food item for the lizards, and the elevated rims of the ant nests provide shade and basking sites. Seasonal emergence, following 3-4 months of hibernation, begins when ground temperature reaches about 19°C. At this temperature the lizards head-bask, emerging fully from the burrow when body temperature is raised to about 22°C. Under these conditions the dominant males emerge and establish territories in mid-August. Basking postures are adopted to raise body temperature to 37.5°C (eccritic temperature determined in laboratory tests). In the field, behavioural thermoregulation maintains body temperature at about 39°C during higher air temperatures. If temperature cannot be held down within this range, the lizard retreats to the humid Jayer below the dry sand in the burrow zone. Within the population, dominant, sub-dominant and subservient males can be recognised by behaviour and coloration during the breeding season (September to December). Among the females, two breeding groups, related to time of hatching, occur. Sperm retention is evident in one of these groups, in which ovulation occurs about 2 months after fertilization. Sexual dimorphism in relation to colour pattern is not thought to be the basis of sex recognition since colour changes occur in both male and female. It seems likely that acute perception of size difference is the basis of sex recognition. STUDIES ON THE ECOLOGY OF THE AGAMID LIZARD AMPHIBOLURUS MACULOSUS (MITCHELL) by F. J. MircHi.i* Summary Mrrcuece, F. J.. 1973. Studies on the Ecology of the Agamia Lizard A.nphiholurus maculosas (Mitchell). Trans. R. Sov. S$. Aust., 97 (1), 47-76, 28th February, 1973. Amphibolarits maculasus (Mitchell), the Lake Eyre Dragon, is restricted to arid salinas in the northern part of South Australia. The lizards live near the margins of the salinas where a suitable burrow area of fine, wind-blown sand underlies the buckled sali crust. Their essential refuge from the harsh environment is in the permanently damp sediments which occur below these dry aeolian deposits underlying the salt crust. Preliminary laboratory experiments suggest that this lizard has a high temperature tolerance (CTM 48.9°C) and low evaporative water losses (1.1 mg/g/hr at 37.5"C). The harvest ant. Melophorus sp., which occurs in the same habitat, is an important food item for the lizards, and the elevated rims of the ani nests provide shade and basking sites. Seasonal einergence.follawing 3-4 months of hibernation, begins when ground temperature reaches about 19°C. At this temperature the lizards head-bask, emerging fully from the burrow when body temperature is raised to about 22°C. Under these conditions the daminant males emerge and establish territories in mid-August. Basking postures are adopted to raise body temperature to 37.5°C Ceccritic temperature determined in laboratory tests). In the field, behavioural thermoregulation maintains body temperature at about 39°C during higher air temperalures.. If temperature cannot be held down within this range, the lizard retreats to the humid layer below the dry sand in the burrow zone, Within the population, dominant, sub-dominant and subservient males can he recognised by behaviour and coloration during the breeding season (September to December). Among the females, two breeding groups, related to time of hatching, occur. Spetm retention is evident in one of these groups, in which ovulation occurs about 2 months after fertilization. Sexual dimorphism in relation to colour pattern is. not thaught to be the basis of sex recognition since colour changes occur in both male and female. Ut seems likely that acute perception of size difference is the basis of sex recognition, CONTENTS 1. Introduction 2.00 2 ee AB (2) Humidity -_ [eee = Cao 4 . 49 (3) Salinity Po «te» no 256 4 Pea ane Metnede ace 7 ag 4. Food and Predation . an L 54 (2) Laboratory data... .. 30 7. Flooding of the Habitat... 58 3. Morphology of Amphibotyrus maculosus 50 8. Activity patterns and Thetmoregutatian 5k 4. Habitat and Distribution a 50 9. Survival in the Preferred Habitat — 4f The habitat of the Lake Eyre population Tolerance to temperature and water slress 6/1) a ane peant s 3 10. Establishtnent tnd Defence of Teericory é burrow zone ..,, Sete ate oth the a Sra be, 62 (3) The “wet” salt zone... .., -. 51 4 A The Lake Callabonna population... ... $1 11. Reproductive Behaviour ee The Lake Torrens population - .. 52 12. Sex Recognition ... .., 65 2 Bbyesal panier OF Fie Sasa ie oa 32 13. Growth Rate and Reproductive “Cycle ff 5. Microclimate of the Hubitat ._ 53 !4 Acknowledgements =... 67 (1) Temperature, to oes ae 653) OSL References cor “Erte cto By. See tue “EG *Late of the South Australian Museum. This paper was compiled from the late F. J. Mitchell's draft manuscripts and ficld and laboratory notes by Ann Mitchell (Department of Botany, University of Adelaide. S. Aust. 5001). 4h FE. 3. METCHEL1. 1. Introducton Araphibolurus maculovas is a highly adapted lizard, restricted in distribution to the salinas of the Lake Byre Basin in the north of South Australia, It was first collected in 1929 by C. T. Madigan, who lodged with the South Australian Museum 20 specimens taken at the southern end of Lake Eyre Nerth in the area now known as Madigan Gulf. These ear- less lizards were identified as a variety of Tympanoeryplis lineata by H. M. Hale, then Director of the South Australian Museum [in Madigan 1930). In a revision of Tynpanocryp- tis, a genus of “earless” dragons, Mitchell (1948) described the lizard as a new species, T. maculosa. Subsequent ostcological studies (Mitchell 1965) showed that the uffinities of this species lie with the genus Amphibolurus and that it represents an extreme speciulization within the venus. The enclosure of the t¥mpanic mem- brane, which had. led to its assignment to lympanocrypis, was cansidered likely to be i secondarily developed Characteristic, This may be an evolutionary adaptation to burraw- Ing in dry sand, and may have arisen on more than one occasion in agamid lizards. Lake Eyre, occupying an atea of 93500 km, is the largest of several extensive salinas in the arid. north of South Australia (Fig. 1), lying aL the ‘southernmost and lowest end (14 m below sea level) of the Lake Eyre Basin, This Basin lies within the 125 mm isohyet in the driest area of the Australian continent. The usually dry river systems draining towards Lake Eyre serve a catchment area of over 1,300,000 kn*. Some of this catchmenr lies within areas of comparatively heavy und regular rainfall but only under particular cir- cumstances does sufficient water reach Lake Evre to fill the Lake. Following exceptionally heavy summer rains in western Queensland in March 1949 and March 1950, Lake Lyre by September 1950 had filled with water for the first Lime in living memory. Scientific surveys, sponsored by the Royal Geographical Society of Australia (South Australian Branch) and led by C, W, Bonython, were carried out until the Lake had again dried out by November 1952 (Bonythan 1955, 1956, L960}. During this period the lizard was again observed and collected. [ts ability to spend long periods foraging on the oper surface of the salt crust of the Lake, withstanding both predation und desiccation, aroused oonsiderahle interest, In 1964, Donald Campbell successfully uttempted a land speed record on the surface of Lake Eyre, In order to gain access to the solid salt crust, a Causeway was constricted from the shore-line across the maryinal zone where the salt crust is thin. The track to the causeway permits vehicular access to the shore- line, and the causeway itself, projecting west from Prescott Point at the tip of Sulphur Peninsula (Figs. 1, 6), has subsequently served as a natural “trap” and developed a population of these hezards suitable for behavioural studies in their natural environ- ment. A study area was sett up at the cause- way, where meteorological observations and records of hehavioural responses of 2 marked population of the livardy were made during visits between February [965 and October 1968. This. paper iy bused lurgely on field obserya- tions of the lizard an Like Eyre, together with briefer studics uf populations on other inland salitas. These field observations were sup- potled by vivarium studies at the South Aus- tralian Muscum, Preliminary experimental work is reported bnefly. 2. Materials and Methods (1) Field? Studies The ecological simplicity of the habitae and the lack of a predjtor sense itt A. macnlosus make it an attractive animal for study once problems of distance, inaccessibility and try- int werking condilions ate accepted. The lizards are very alert and hecause of cryptic coloration almost impossible ta detect except during their sudden, rapid movements to main- tain a few metres distance from un approach- ing observer. During the breeding season, however, territorial challenges, fighting and mating continue uninhibited’ by close-range observation. Early in the field studies some 10 km of shoreline were surveyed, but later observations were resiticled to the causeway population und all meteorological records reported here were taken in that area. In all, L6 trips were made lo the study area during the period February 1965 to October 1968, Average time spent at the study atea on these trips Was 7 days. In addition, during September and October 1967, an extended survey Was made of the major salinas extend- ing in an are around the northern end of the Flinders Ranges. regurded us potentially suit- able habitats for the Hzards, ECOLOGY OF AMPHIBOLURUS MACULOSUS 4g Field data have been derived from several sources. Continuous temperature records of air and sand at various depths were obtained using an EILCO thermistorised twelve-outlet, twin channel. recording thermometer, while single readings were taken with a Thermophil elec- tronic thermometer. Rectal temperatures were obtained with a Schultheis, quick-reading mercury thermometer, All instruments were checked and calibrated in the laboratory before each trip. Relative humidity was variously measured with cobalt thiocyanate papers, Fig. lithium chloride cell equipment and = whirling psychrometer. Behavioural data were obtained from direct observation and from the marking and re- Capture of specimens in the causeway popula- tion, at Prescott Point. Quadrats were marked out along the edges of the causeway and move- ments of lizards in relation to these areas were recorded during the period of study. Lizards were permanently marked by toe-clipping, and colour-coded For rapid identification of marked specimens in the field. LAKE la CALLABONNAT=3 * © MARREE 1. Map showing the major salinas of northern South Australia and the known distribution of Amphiholurus maculosus. Inset map (upper left) shows portion of Madigan Gulf (the type logality), and the location of the causeway at Prescott Point which was fhe main study area. A hlack square indicates areas in which populations’ of A. maculasus have been observed; a white square indicates arcas where survey of the salina margins revealed no specimens of A_ macn- losis. Sh F. J. (2) Labonuery dare Experiments on thermal criteria and tem- perature ltolerunce of A. maculosus were caried out in an oven preheated to 45°C. Regular lemperuture increments of 1°C were made at § minute intervals Rates of water lass were derived from e¢x- periments carried out in a thermostatically controlled, Wauter-jacketed incubator under temperature conditions controlled to =0,5°C. ‘Yhe test chamber wus also desiccated over silica gel to ensure a relative humidity of less than 4% at all temperatures. Experiments to deterntine water loss through the integument were undertaken with the vent of the animal sealed with waterproof adhesive lupe amd the head inserted through a_ thin rubber membrane across the mouth of a con- tainer partly filled wath silica gel to absorh avy Water lost through the ittegument. The silica gel was overlain hy u piece of thin card on which the lizard’s body restect. The test animals were acclimated for at least seven days to coriditions involving the daily allainment of their maximum voluntary activity temperature (39.8°C), Animals were tested hetween 1000 and (500 hours during their period of maximuin activity. For long-term behavioural studies, a ter- rarium was set up which successtully simulated lake shore conditions. A layer of gypseous clay. maintained in moist condition, was aver- lain by 15 cm of drv sand from the lake shore, Over fhe sand, pieces of consolidated salt crust provided a surface similar to the burrow zone area. Both light and heating were provided by au battery. of high-power incandescent lamps mounted under an adjustable hood. ‘Time switches controlled day length, and the posi- tion of the hood controlled the maximum temperature, Strong correlation between field observations and laboratory tecords was Found for daily and seasonal activity cycles and the onser of reproductive activities. 3, Morphology of Amphibolurus macplosus Amphibolurus maculesus shows several features OF morphology, physiology and be- haviour Which reftect its adaptation to arid silinas, Its dorsal surface is white to very pale grey with u row of very dense black blotches on either side of the vertehral line, Dorsally and laterally there are smaller black and rusty-hrown pigmented areas, This colour MITCHELL pattern gives excellent cryptic coluyralion on the salt surface, the dark areas blending with the shadows of small holes and pinnacks on the rough salt (Figs. 9, 10, 15). The ventral wurfuce is white with a dark streak cxtending longitudinally along the centre of the throat to the gular fold, Colour variations related to the environment, ani the striking colour pat- terns developed during the breeding season will be discussed later in this paper. The adult male attains a total length of about L1.5 cm (snout-vent length 7 cm}, the adult female being smaller ut about 10.0 cm (snout-vent length 6 cm). The eye ts small and deeply sunken and is protected from salt glare by promiment ser- rated eyelids with dark pigmented Jinings (Fig. 4), The nostrils, while showing a circular external opening, open inte the nasal cavity by only a narrow slit, directed forward and down- ward, This structure prevents the nasal pas- sages from becoming blocked when the lizard burruws through joose sand. Speci! nasal stwucture has been described by Stebbins (1943) in the Americun venus U/ma, which is a sand-burrowing form. He has shown (Steb- bins 1948) that other American iguanil genera including Uru, Helbroakia and Phrynesonea, all of which habitually burrow in loose sand. have similarly adapted nasal structure. 4, Habitat and Distribution The type locality of 4. meaculasies 1s Madi- gan Gulf, Lake Eyre North, out from the mouth of the Frome River. The species is widely distributed around the southern shore- line of Lake Eyre North and around the nerthern ind south-evstern shorelines af Lake Eyre South. Throughout the study every oppor- tunity was taken ta search other lakes for additional populations and practically all of the major salinasy in che State were at Jeast cursorily cxamined for signs of habitation by these lizards. Two additional populations were found: uw population in the saline areas at the southern end of Lake Callabonna and extending soulhwards through the salt chan- nels inte the northern tip of Lake Frome, and nother population along the north-western shoreline of Lake Torrens, Fig. 1 shows the area searched, the localities from which speci- mens have been taken, and the range over which this species is known to occur. The geomorphology and the history of land- forms In the Lake Eyre Busin have been dis- cussed by Wopfner & Twidale (1967). Evi- ECOLOGY OF AMPINBOLERUS MACULOSUS 3| dence from fossil deposits suggest that exten- sive areas Of brackish water or saline swamps existed Within the basin from mid-Tertiary to the end of the Pleistocene. The ongin of the salt in Lake Eyre has. been subject to debate but i stems likely that both cyclic sult and connate salt, accumulated from waters brought inte the basin from the extensive drainage system, have contributed (Bonython 19546; Wopiner & Twidale 1967; Twidule 1968), The present isolated populations of A, mracy- fases, which although spatially widely sepa- rated ure virtually morphologicylly — indis- tinguishable from ane another, may be relict from uw more widespread species evolved in association with the shoredines of the Sarge brackish lnkes and swamps that were a feature of the Lake Eyre Basin during Pleistocene and early Recent periods. THE HABITAT OF THE LAKE EYRE POPULATION The habitat within the study area can be divided into three distinct zones, the “beach”. the “burrow zone” and the “wet salt zone” (Fig. 5). This zonation can be readily identi- fred throughout the distribution of the Lake Eyre population examined, bit is much less distinct in the area of ibe other two poepttly- tions. 1. The beach; tn tie area along the southern shoreline of Lake Eyre North which was most intensively studied, the beuch is backed by near-white sandhills varying from low consolidated hummocks stabilised by low shrobby vegetution { Nitraria, Seaevola) to high drifting dunes encrouching upon the lake. In Many arcas low cliffs varying in height from about a metre to upproaimately 12 m above the lake hed expose Recent to Cretaccous sedi- ments to face the lake Continuous wind erosion transports large quantities of gypsi- ferous clay and grit and other aeolian fines out over the beach and on to the surface af the lake, The beach is usually a narrow strip of consolidated sand Frequently intermixed with wreas of very coarse sand and pebbles. In areas where it is not overlain by recent drift it remains damp during the cooler months. Typical pebble beaches occur in some areas and the height and form of some of these beaches suggest sustained periods of strong wave action in the very recent past, 2, The burrow zone. This term has been adopted to cover the zone tn which most of the activity of the lizards takes place. It con- sists Of un trea of distomed, dry, crusty sur- face, varying From a few metres wide (im areas where flooding upproaches close inshore or where little pypsiferous drift is brought out by the prevailing wind) to 400-500 m wide in stidom-flooded embayments where wind- drifled deposits have accumulated on the sur- face (Fig. 5), This 5-15 em thick layer of fine gypsiferous clay and sand rapidly dries out and in doing so cxpands and distorts the Salty crust which Sorms over the top of i. In section, this provides a burrowing substrate consisting of an irregular, salt-impregnated. crust up to 2 em thick, lying aboye approxi- mately 10 em of fine, dry, windblown sedi ments underlain by sand which is kept con- tinvally dump from the water-table 40-70 em below, The lizards break through the salty crust at a weak point and then literally “swim” through the fine mobile scdiments below until they encounter the high humidity associated with the damp consolidated sand at lower levels. They remain there until their re-emergence js triggered hy rising temperatures or some internal stimulus.. They follow the thermal gradient hack to the surface, frequently emerging at a different point to that of entry, 3. The “wet" salt zone: The solid salt crust of the lake varies from about 2 cm in thickness in inshore areas to about 40 cm in thickiess fowards the centre of Madigun Gulf. This crust, overlying wet gypseous clay. becomes distorted and buckled as the salt recrystallises on drying out (Figs, 7, $). Although most of the activity of this lizard takes place within 250 in of the shore, both the lizards and the nesta of the ant Melopkorus sp. (their princi- pal item of food) have been observed more than 1400 m from the shore linc, During the territorial season, many young subordinate mules are forced to live outside the burrow sone and are frequently found well offshore. While liltle weight can be placed on the salt surface without bringing water to the surface, the actual surface “skin” js dry most of the lime except in cerlain effiorescent areas close to shore which are continually damp. Relative humidity readings using cobalt thiocyanate papers set | cm off the salt under a shield. gave readings as high as 55% over these efflorescent areas, bul in other areas the read- ing was below 15% and equalled the reading at 100 cm above the surface. THE LAKE CALLABONNA POPULATION Essentially the same conditions prevail as at Lake Eyre. with the lizards living around the 52 Fr. J. MITCHELL. southern margins of the lake on isolated patches of aeolian drift in association with dry saline crust, A suitable habitat is not present in northern parts of the lake, where fresh water from the Strzelecki Creek has leached the bulk of the soditim ancl catefum salts from the surface deposits and the water table is deeper hecause of extensive Recent lacustrine deposits on the surfuce. THE LAKE TORRENS POPULATION The surface of Lake Torrens is wet and muddy und the take frequently contains water. As a consequence the population has adjusted its behaviout to living amung low vegetation along the immediate shoreline and upon jow- relieY islands covered with chenupodiaceous shiulbs. PHYSICAL FEATURES OF THE BURROW ZONE Field and laboratory observations suggest that there are three essential habitat charac- teristics Which influence the cistribution of this lizard, |, A surface crust: Specimens placed in a laboratory cage containing either loose sand ur consolidated sand lacking a surface crust were upable ta burrow, ‘They were only able to scoop oul a shallow depression, Several ficld observations related to this were made during the 1952 flooding of the lake when most of the lizards were forced onto the damp beach. Some did succeed in finding crusted areas back among the veyetation but several lizards were found im shallow depressions against drift- wood wong the beach. Presumably the sur- fave crust is casential in providing initial pur- chase against which these lizards start their “swimming” procedure in burrowing through the sand, Vhe consolidated surface crust need no. Hecessarily be saline and in fuct, gypsiferous sediments hus Logether by filamentous blue- green algae may well have provided a suitable hafritat surface over wide areas in the past and may prove io be aw contributitig factor at present. 2, A layer of fine dry sand (and/or clay) about 10 em thlek under the erust: In order to pro- vide adequate insulation from the extreme heat of the summer, the fine sand or sand« yypsiferous clay mixture must be dry and about 10. em thick. It is probably important that the sediments contain pypsum to promote expansion and rapid drying after wetting. 3. A constant source of humidity Jor Me re- treat: Because of the water balance problems inherent in living upon a salt surface sub- ject to exlrerne lemperature, mw is essential that the environment provide a refuge in which both evaporalive und respiratory water Josses be minimised during the periods of retirement underground. The sediments al about I) cm helow the surface crust must be permanently damp, PRESENT KNOWN DISTRIBUTION At most of the localities examined along the shore of Lake Eyre North and Lake Fyre South, lizards for “signs of their presence) were observed whenever a combingtion of the three factors described above were found. This applied equally well to Lake Callabonna ex- cept that suitable habitat there is much more limited. Most of the northern part of Lake Callabonna and Lakes Blanche and Gregory have uo very friable surface deposit of fine gvpsiferous clay which is not bound hy a surface crust. This is not a suitable habitat. Lake Torrens lies on the “weather” sie of the Flinders Ranges and is therefore subject to more frequent flooding than the other lakes around the northern end of these ranges. The lake surface is therefore permanently wet and does not provide a suitable habitat, but at the northern end and particularly along the western side, suitable conditions occur along the actual shoreline and upon Jow insular greas where the pale gypsiferous clay supports sparse halophytic vegetation, Many of these arens dry out during the warmer months, and form a suitable habitat with a distinct surface crust underlain by varying depths of dry pale yellow to red gypsiferous clayey silt, This habitat i exploited by the Lake Torrens population, Specimens have been collected up to 275 metres back into the vegetated zone away from the margin of the lake, Chher Jakes examined were Lake Harris, Lake Gairdner, Lake Everard jind Lake Hart (Fig. 1). Although knowledge of the shore- line conditions gained during this survey was very fragmentary, the yeneral information gathered is considered adequate lo suggest that if any additional populations are found on any of these lakes, they will not be found living upon the surface of the lakes as at Lakes Eyre and Callabonns, but along the margins as at Lake Torrens. The sufface conditions of these Lakes ure similar to Lake Torrens, the surface being too wet le support the ants ECOLOGY OF AMPHIBOLURUS MACULOSUS 52 (Melophorus sp.) which provide the principal item of diet for these lizards; these ants, or other species of similar burrowing habit, are restricted (a the shore-line areas. In many of the Jakes, the ecological situation occupied by the unis ut Lake Eyre is taken over by 4 species of Fighting Spider (Geolycosa sp.). Cicindeline beetles are also frequent and active predators over these damp lakes and in part Teplace the ams as surface scavengers, They dig vertical burrews into the damp muddy surface an@ huve only been seen ut the Lake Eyre stiidy area when layers of fresh silt from fioodjags were overlying the salt: 5. Microclimate of the Habitat A. macilosus has a strict preference for the Taargins of the salinas and does not invade the white sandhills despite ts competitive daminunce., in cage experiments, over the only agamit species which occurs there (Amphibolurus pictus Pevers), It was noted also that 4. pictus makes burrows over a metre Jong and up to 20 cm deep in mid- summer, despite the fact that its thermal tolerances are only slightly inferior ta those of A, maculosus (see Table 2), This suggested that the lake surface environment may have some thermal advantage over the adjacent sandhills, Climatic conditions prevailing within the habitat were studied in an effort to deter- mine the reason for the strict habitak prefer- ence and also to provide a foundation for an analysis of the activity and behavioural pat- terms observed, (1) Temperature Using the thermistorised recording ther- mometer, aa allempt was made to compare the temperature profiles of the sections. of the burrow zone preferred as a refuge by the lizards with parallel situations in the adjacent sandhills. Comparison between sum- mer (February) and winter (July) temper- alure patterns for both the burrow zone area and the nearby white sand-dune area js given in Fig. 2. Summer soil temperature profiles for burrow zone and sand-dunes aré shown in Fig. 3, The data obtained proved difficult to evaluate, probably because of the difficulty of obtaining strictly comparable test. sites, The ground humidity varies from place to place with the local soil structure conditions and the thickness of the surface drift, and the extent to which the ground water has pene- trated towards the stirface also varies. It is nut possible to assess these fuctors without breaking the surface crust and thereby dis- turbing the stratification of the protective layers winder which the lizards normally rest. Therefore, while the lizards were found con- aistently to prefer to rest on or just in the damp sand underlying the mobile dry sand, it Was seldom possible to determine wher the tip of the thermisior probe was lying in this same position. Aljso the protective value of the surface soil was greally reduced by local #ain which increased its conductivity, All of these factors reduce the comparative value of the data. "The data, however, do allow iwo conclusions to be drawn with reasonuble confidence. Firstly, during the cooler weather when both the burraw zone deposits and the adjacent sandhills are damp to the surface, the thermal characteristics are essentially the same. Second. ly, in midsummer the temperature at average refige depth (10 cm) in the burow zone, probably due to the thermal capacity of the water table 40-70 em below, is lower und subject to less fluctatlon (30=1,5"C) than the temperature in an equivalent situation in the adjacent sandhills (34%4°C) (Figs. 2, 3). {2) Humidity Surface temperatures were recorded using a contact thermistor and a Thermephil elec- tronic thermometer. Because of the salurution of the lake floor right to the surface and the periodic appearance of free water on the sur- face of the more thickly salt encrusted area, it was anticipated that evaporative cooling would contribute to lowering sutface temper- ature of the Jake and raising humidity, particu- larly at the “living level" of the lizards (1 cm), both being features which would improve its suitability, as a habitat during the warmer months. However, careful testing with the thermistor probe revealed the acttial surface of the “wet” salt to be dry and at the same temperature as the crust in the burrow zone and ue sand in the sandhills. Similarly, tests with cobalt thiocyanate humidity papers at 1 cm and 100 em above the lake surface and 100 em above the adjacent sandhill sur- face usually gave the same treading, Over the temperature range 30 to 40°C, during which lizards coukl he expected to be active over the “wet” salt surface, the readings were usually below the minimum sensitivity of the paper, mdicating relative humidities below 15%. a4 F. J. METCHELL Humidity teadings, derived from each af the sources described ubove, varied from Jess than 5% to 55% refative humidity. ‘The higher readings invariably followed light rain or thundery conditions and were the same for sandhills and lake surface sites, As air lemperuture increases each day, over the solid salt crust, the “wet” salt begins to “sweat” und brine appears at the tips of small, self- sealing, salt pinnacles. Due to the high tem- peratures and high evapurative rate it ts likely that. any humidifying effect of this brine is restricted to a microtayer, of perhaps only a few mm, just above the evaporative sur- face, However, tf was not possible to detect higher humidity over the “wet” salt surface and this is possibly due to inadequate instru- mentation, 13) Saléstey The salinity: of the wind-blown silts deposi- ted in the burrow zone varies with depth. Salts dissulved out from the superficial layers were 7-11% of the silt; 3-5 em down, 4-8% and 5-10 em down, 3-4%. Below this level the salinity steadily increases again up lo saturation at the water table 40-70 cm below the surfate, The decrease in salinity nearer the suftface is probably due to the recent ofigity of the surface deposit and to condensa- tion dlong the line of demarcation between the permanently dampened sands and the overlying dry sediments leaching the salt out over a period of time. The lizard} normally rest in this zone of lower salinity but whether this is of any advantage is: unknown. The sand along the foreshore also contdins 2-4% salt and the observed salinity stratification may he due to an increuse in surface salinity hy wind drift from the sandhills rather than to desalination of the intermedinte luyers. Several small areas of white efflorescent salts were found just outside the burraw zone and these areas are continually Josing water la the atmosphere, Although no. hzards were ever ubserved using one of these areas on a hot day. the large number of fecal pellets Fig. present on and around them suggest that their thermal sdvantages may be ulilised by the lizards. The surface temperature of such an area of about 3 m* near the main study site was compared with that of the surrounding salt and found to be up to 9.5°C lower It appeurs that the Jake surface confers no advantages upon an inhabitent, either in terms of surface temperature or humidity, over the condition prevailing in the surrounding sand- hills. Despite the abundance of free saline. water throughout the habitat it may still be inadequate to prevent the high evuporulive rate [about 220 cm per annum (Bonythen 1955)] from creating sufficient dry hygroscopic salt throughout the habitat to place greater strain on the water balance of this species than other desert-adapted lizards. The permanently damp layer under the pro- teelive crust in the burrow zone provides. a high humidity retreat into which the hzards ean Tetire overnight or, if under social or environmental stress, for much longer periods without endangering thew water balance. This is regarded as the key factor an restricting the species Wy the marginal urcas of the salinas. 6. Food and Predation The main food source for A, macilosus is the harvest-ant, Melophorus sp. In addition to providing food, the nest-mounds of these wots are important “features” in the generally featureless habitat, providing lookout points, basking sites and the only source of shacle. Colonies of Melophorus generally occur on the “wet-salt” surface usually within 750 mm from the beach zone; preference is shown for areas where the salt-crust is no more than 2 em thick and underlain by telatively clean sund down Lo the water-table 40-70 em below. The colonies are regularly spaced over the tuke surface, each being about 10 m equi- distant from the next (Mig. 8}, Investigation of a nest revealed a setics of upper gsuallerics just beneath the sult crust and i single verticy! hole z0ing down about 40 ein to a second set 2, Comparison between summer and winter thermal characteristics of the borrow zone and adja- cent While sand dunes, Figures from continuous recorder traces of temperature were platted ut 40 minute intervals. ~ temperature at -10 em -——--—- lomperuture at -l cm -- +). oir temperature at 40 em above ground 4A) Burrow zone temperatures over 34 hour periods in February, 1965 and July, 1966, Tem- Peroture range at--10 cm for the February period was 3.5°C, about a nivan of 33.6°C. (B) Sand dune temperatures. over 34 howe perinds in March, 1965 and Tuly, 1966. Temperao- thre range al -10 em for the March period was 1 1L.5°C. about 4 mean of 34.6°C. ECOLOGY OF AMPHIBOLURUS MACULOSUS 55 A pe Pky 7 ead! xt teal é ~ o c N ¢ ¢ ‘ é | ¢ \ 7 4 LN eo -40 r “4s Loe u fy ut Re fat é a tan L < Le / —T te ee : f ¢ a yo vt ay as mee ee ee ! re fy lark 2 E ay 22% FEBRUARY 1965 Ore cee ae an aad M~30 oF he Pee . : P- a . or ’ E-s Ls s woot ‘ . a Rare t U; R Fete Ee - a. oAP20 er ate f Ls é i ra ON / { sf a ¢ we a a ee 19 JULY 1964 har a 20" é 8 10 12 14 16 18 20 22 24 2 4 6 8 10 12 14 ee ee Se ee a ee! ee ee oe es en re” jee i L =| = ! | fe D Re | homeo, | TIME - HOURS | 40 2°49 MARCH 1965 T E ME P E R A T “7S U e ie R PY te °C 23" JULY 1966 Tee ee sry Pull 2ath HHO ys Tee 6 8 10 12 14 16 18 20 22 24 2 4 é 8 10 12 14 be L i i He ees 1 L ni Ly gt AP estoy ke L be Ves L 4 TIME - HOURS FIG. 2 SH FJ. MITCHELL of galleries at or slong a consolidated layer of clay just above the water-table, The Gon- suruction of these galleries produces, on the surfuce, a distinctive crateriform mound up to 2) cm ja height. The sand below the salt crast is usually covered by a fine layer of clay Which probably accounts for the reddish- brown debris, brought from below, being in marked contrast to the while salt crust, At any time, only 9 small proportion cf the total wumber of nests contain active colonies, The ants show linited activity dur- ing the day, appearing at the surface only to deposi sand grains from the workings below round, In yicw of the limited aboye-surface activity of the wnts, it has been suggested (Madigan 1930) that Melophorus baryests micro- organisms either in the salt crust (blue-green algal cells) or in the damp sand above the water table (Dunalielle spp.). The nests usually, however. contain insect remains. and the ants have been observed gathering bodies of insects trapped on the sult. Probably most foraging uclivily by the ants oecurs at night. A. niculosus, also, is an Opportunistic feeder and when other insect life is available on the lake surface, the lizards feed on a wide ranve of different insect species. On most nights numbers of insects are stranded on the salt. surface. Their presence may be explained in several ways, With jin, offshore wind many insects may be blown out over the lake; others may be attracted by the rise in humidity over the lake surface af night; aquatic insects (particularly on moonlit nights) may mis- lake the white lake surtuce for walter. Overall the Jake surface produces a vast “white sheet” effest — un cimmmonty used form of insect trap—and many insects are Ifapped on the hygroscopic salt surface and killed when temperature increases next morning, During ihe spring months, September—November. vast quantities af insect Jile may occasionally be stranded on the lake surface. The bodies of insects Which have been neither captured by 4... mueu/osny nor later scavenged by Melo- hig, phorus become incorporated within the sur- face salt layers. it ls Of Intevest thal the characteristic insect fauna developed in the vegetation of the shore- line and sand-Aills is rarcly stranded on the salt surfuce of the like, while the majority of species stranded on the salt are seldom seen about the shore. The period of greatest feeding activity of A, maculasus (February to April) frequently coincides with drought conditlons in the sur- rounding country, and consequent limited supply of windborne insect life. Tn view of the limited number of ants active on the surface, the lizards nist lorage out over the lake surface for long periods at high temperatures. The lizards dig into the sides of the ant nests to retrieve ants from inside, and the more frequently visite ant-nests closer tnshore become very battered in appear- ance, Shallow depressions scraped out at the base of the nests provide small areas of shale intu which the lizards may retreat. The Lake Dyre population ol A. maciulosus displays no response to overhead predators, relying lor safety on their cryptic coloration, The only possible protective cover on the lake surfuce ts provided by buckles and cracks in the surface of the salt crust (Figs, 7, 13). Although these would seem to provide ideal reweuts they arc tarcly used by the lizards. The crystalline swit in ihe erust provides a “glasshouse” eflect and the temperature below the ¢mist may be several degrees higher than the surface of the salt. When pursued aver the surtace until exhausted, the lizards are more likely to come to rest in the shade of like pursuer than to retreat helow the salt crust. There is Jittle evidence of other potentiil Predulors moving ot across the salt surface, Hawks. constitute one Of the main predators of A. piceus from the sandhills adjoining the Jake. On several ovcusions dead specimens of A. picts have been observed well off-shore on the fluke surface. Presumubly these have been dropped by hawks. The fact that these 3, Yautechrones (soil-air temperature profiles at. different times during the day) recorded on 6th March, 1965 for (A) burrow zone area and (B) sand dune urea. Differing thetmal characterts- tics of the two localitics result in the more rapid and greater heating in the sand dune area, At—I0 cm (averave burrow depth of A. muculases) in the burrow zone there is a temperature range from 30,9 to 35.6°C over the timc period recorded. At the same depth in the sand dune area there is a temperatitre ratige from 31.4 to 4L,.4°C over a similar time Interval, In (B), due to the limiled range of the thermometer used (calibrated up ia (20 F (49°C)), no figures are avallable for (he 2 em and 4 em depths at ihe 1120 and 1515 readings. Field notes recorded that, at these times and depths, the temperature Was “12Q°F-+> nd rising rapidly”. ECOLOGY OF AMPHIBOLURUS MACULOSUS 4 se } ¥4 57 SURFACE ~1 2 DL E |} E 7 0630 1100 1600 H 25 30 35 40 45 50 — 1 1 aoa 2 —- lhe sie, ® re 1 Sy 1“. 1 TEMPERATURE ‘°C i> Z \ \ SURFACE + - = a aa si |} I as 5 0600 Q?30 TIaAymg —1 N 3 po pe) 10 ? 1120 1815 25 30 35 40 45 50 t . i P af t TEMPERATURE ‘°C FIG. 3 38 BF. J. MITCHELL captures have not been retrieved would sug- west that the glate From the Jake surface may confuse werial predators. 7.. Flooding of the Habitat The periodic flooding, either of the whole ot Luke Eyre or, following more localised ruins, of restricted areas, must affect both Melophorus and A. maculasus: Melophorus colonies withstand flooding for consideruble periods by becoming sealed off below the water. As water disappears from the lake surface, the colonies soon “break out” wand tework the galleries and nest. The shape of the above-sutface mound would give protection to the opening of the nest during light flooding. When the nurmal burrow zone is Mooded, A. maculosus retreats to the shore line and lives, precariously, in the sand there. The lizards are frustrated in atlempls to retire underground since there is no consolidated crust. to provide Jevernge for burrowing, and they have no refuge from predators such as the Ground Goanna {Mararnus gouldii Gray) ugainst which they have adequate protection in their narmal habitat, Among the lizards forced ashore by flooding, colour changes occur in which the backgtound colour of the lizard becormes a deeper grey and the areas of black and rusty-brown pigmentition become more numicrous and intense, giving 2 speckled appearance more similar to the pebbly heach sands, At times of flooding, large nuim- bers of Silver Gulls (Larus novae-hoflandine Stephens) ure attracted to the arca and these probably constitute the greatest predation hazand tor A- maculovay. An interesting response 10 flonded conditions has been observed in A. maculosns, During winter at fow ground temperatures (down to 16°C) the lizard is in torpor. In vivarium experiments at low ground temperatures, (14- 16°C}, flooding of the substrate aroused lizards which had been belew the surface in torpor for 3-4 weeks. Emergence to the surface involved a greater degree of muscular ¢o- ordination than is usually shown at these temperatures nnd may be triggered by lack of oxygen. Inflation of the body when it emerges from underground ensures that the lizard floats on the surface of the water. It would appear possible that such a reaction would assist survival of the animal in face of encroaching floadwatets. Localised areas of water in the lake show marked response to changes of direction and velocity of wind, A flooded inshure area may, within a few hours, appear us an exposed sull surface anil vice versa, This dust impose uidditional problems in the re-establishment of both Afelapherus and A. maevloases in their preferred habitat, 8, Activity patterns and Thermoregulation Like other ectothermic animals, the activity af Amplibolnvus macelesus depends on temperature. The lizards show definite be- havioural fesponses al cerlain temperatures and these responses serve to keep the body temperature within a preferred activity range. Throughout the season of lizard activity. varta- tions occur in the means and ranges of these temperatures, These variations, imposed by the uge and sex of the particular lizard and its position in the social structure of the popula- tion, are considered later, The basic range of temperatures associated with various wetovities. summatised in Table 1, fs dictissed here During the winter months (May to Augusr)- A. maculosasy remains in torpor helaw ground Emergence threshold air temperature is 19°C, at which temperature there is early season emergence (August-September). under stress of hunger and drive for the establishment of terrttory, in males. Ac this temperature only the head of the lizard is thrust through the salt crust. It is darkly pigmented in the pineal tegion and the eyelids are extended, indicat- ing accumulation of blood in the cephalic sinuses, The morphology of venous shunts in the cephalic region, and their role in head- hody temperature regulation, have been described for Pkrvnetame cornutum by Heath (1964, 1966), Although the anatomy of the head of A. mtack/osus has not been examined, there is similarity in head-basking hehaviour hetween this lizard and PArynesoma, Which is Known to use this aid to rapid stimulation of the central nervous system and elevation of body temperature. It seems likely that A maculosus usts a similar mechanism. The head-busking position is only maintained until the body temperature is raised to 22°C, at which temperature the body is Fully exposed at the mouth of the burrow, Tt is at this tem- perature that most lizards first emerge for the season in September—October. During early busking stages the body of the hzard is orientated with the back cxposed to the sun (or source of heat in the vivarium), and the body ts inflated laterally and closely ECOLOGY OF AMWPAIBOLURUS MACULOSUS ay pressed to the substrate, with the hind legs spread out flat behind the body in a “swim- ming” position, Under laboratory conditions, with air tem- perature at 23°C, the adult lizards emerged, with eyes still closed, as soon as the lights came on. Within 10 minutes all were fully emerged and awake in the flattened basking position. Within 30 minutes rectal tempera- tures had risen to 30°C at an air temperature of 23,9°C, During summer, mean burrow temperature (al about 10 em depth) is 32°C. Under these conditions daily emergence occurs with first light, and temperature is no longer the cons trolling factor. The basking position is maintained until body temperature reaches 26-27°C, when the hzards first start to move away from the burrow and ate sufficiently co-ordinated to feed. At a body temperature of 32°C, the lizards ure capable of Cull range of movement and activity and, in hot weather, they move out onto the salt crust at this temperature. The eceritic or preferred body temperature, was determined in the laboratory by use of a saw- tooth thermocline. Under laboratory condi- TABLE I dency of A, maculosus in relation te body femtperature j | | | ee | 49,5 °C tothal temperawre uncontratud =48.9°C—CTM f hentine | aso! | 2-43" C omantenee aA = | temorceutatory 40°C - tem neruture —39C—oominiled Lemineraure (lod) | enntan| AIS ervenitictonierature Cab,) 55° | | 26¢>—nn Activity eae 27-289 C—maye frm burriy Huskie range ais Oe 12° C—ful emergande 19% —rarly emergence; head basking tions the top temperature of the basking range is 37.5°C. At this temperature there is re- orientation of the lizard from the positive to negative with respect to heat source, In the Vivarium, the lizards can retreat under-grournd at any time, whereas in the lake habitat, they must return from the wet sali surface ta the burrow zene to retire under- ground, In the vivarium they retreat under- ground at a body temperature of 37-37,5"C, While in the field they remain active on the salt surface away from the burrow zone with body temperature held at about 39°C. Except under very hot conditions, the lizards have a normal activity cycle of about 8 hours per day. This long period of scavenging is correlated with food supply and is necessary lo ensure that they obtain sufficient food. In summer, during, much of this time air and surface temperatures would be over 45°C. At these temperatures the body of the lizard is held high off the salt surface, the only points of contact with the bot surface being the feet and end of the tail. If stationary for any length of time, the toes of the hind feet are Taised from the surface so that there is con- tact only with the limited area of the heel. During thermoregulatory maintenance of hody temperature at ahout 39°C, use ts made of the diversity of substrate conditions pro- vided by the buckled salt crust, of the small ateas Of shade cast by the ant nests and of the few small pieces of driftwood embedded in the salt surface which ate used as elevated perches, Since, during the hotter summer months. there is an established behavioural pattern of daily movement out from the burrow zone onto the “wet” salt crust as the temperature tises, it seems likely that the lizards achieve same thetmoregulatory advantage in this ured. While measurements revealed no consistent decrease of temperature or humidity over the “wet” salt, this may simply reflect the techni- cal difficulty of detecting small changes on the actual surface of the crust. Slight pressure on the “wet” salt crust releases moisture to the surface, accompanied by 4 rapid, transitory fall in temperature due to evaporative cooling (particularly when a wind is blowing). The lizards, by scratching at the ‘surface of the crust, may achieve this same cooling effect for parts of the body in contact with the surface, It is noticeable that AD TP. J. MITORree. during the hot months, which coincide with the defence of territury by the dominant mules, the young males forced to spend con- siderable time out over the salt surface devel- op uccumulations of salt on the digits of all limbs (Vig. 11). There may also be salt encrustation along the ventral surfaces of these lizards. This sale accumulation may be caused by the lizards seratching at the sur- face of the salt crust in allempts to bencfic from any slighl evaporative cooling elects. When no longer able to control body tem- perature by adjusting position and stance, the lizard Must retreat fo the burrow zone and retire underground, In order ta reach the cooler, wet sand Jayer near the water table. the lizard must first penetrate the Joose sand below the salt crust, The upper layer of this loose sond muy reach w temperature of 60°C. A, maeulosus must have a short-term toleranee to this extreme temperature in order to benefit from the hwnid layer below, Wf Foreed to remain active at higher temper- atures, A, wraculosus begins to “pont” at a hody temperature of 42-42.5°C. In this action the mouth is opened wide (Fig. 10), and there is u steady rate of deep breathing at 60 breaths/ minute. Unlike some other lizards (ew, Varanes spp. A, pietus, A. tnermts) there arc no associated movements of the gular pouch during panting in A. muculosts, Tolerance of temperatures. above 42°C, at which thermoregulation begins to break down, are discussed below. Preferred body temperatures and thermo- regulatory behaviour of several other species of Amphiholuruy Wave been described by Bartholomew & Tucker (1963). Bradshaw & Main (1968), Brattstrom (1971), Heatawole (1970), Lee & Rarham (1963). Licht, Daw- son, Shoenwker & Main (L960), and Pranka (1971 a. b). 9. Survival in the Preferred Habitat ‘The habitat preference of Amphibolnrus moculosus is unique among vertebrate animals and many factors would appear to count against survival im such a harsh. extreme environment, There jire obvious problems in maintaining water balance, arising from the hygroscopic salt surface on which the lizard spends much of its time, compounded by lack of aceceys to free water from which to supple- ment its supply, and the need to handle a higher than average sodium intake. (The ants, Melopherus sp.. have uw high salt content (Braysher 1972!) and many of the insects (rapped on the lake surface huve salty encrus- tation on their body and legs), The survival oF an insectivorous animal in a Vegetation free habitat, periodic flooding of the lake. high summer lemperatures, and lack of cover from the sun, are all matters which require spectul physialogicul of behavioural siljust- ment However the liza has the ability Lo &xploil this habjtat successfully. The low rate at reproduction (one to four egeys per female per anium) sugeests that its biology is more than adequate to meet the environmental stresses. As with all desert-adapted animals, behavioural avoidance of environmental extremes (Schmidt- Nielsen 1964) has been shown to be a key factor jn survival in this harsh environment, hut the study also indiested that the enviren- mental stresses encountered require consider- able physiologicul adjustment to ensure sur- vival. The wide scape ol this study has only permitted superficial examination of these adaptive mechanisms. and more detailed studies have been undertaken by other workers, Taleranee 1 teniperadive ane water stress Survival of Aimphibolurus pacniosus in the lake Eyre habilat involves ability to with- stand high temperatures and to cope wilh the lack of free water, Preliminary experiments were carried oul 16 determine some of the thermal critena and rates Of evaporative water Joss. Although the results are based on very few reuclings, the data are presented here since they ure the only records available for this species, Com- parison is made wuh published data tor two ather species of Amphibolurus: A. pictus Peters and A. inerinis (De Vis), Both of these species are widely distributed in desert areas and oecur in the sand dune country ailjacent to Lake Eyre. A. tnermix is generally found in red sand and A. pielus shows preference for white sand. Comparisons between A, plac logs, A. picmn and A inermis are summarised in Table 2, a i Braysure, M. 1. (1972).—-Water and electrolyte balance im the agurmid ligated Amphibolurax mocntosny. (Mitchel. and the structure and function of the nasal solt gland of the sleepy lizard, Trachivdesanrus rugesus (Gray), Unpublished Ph.D- Vhesis, University of Adelaide. ECOLOGY OF AMPHIBOLURUS MACULOSUS él TABLE 2 Thermal criteria and rates ef evuporative water loss for A, maculosus, A. pictus and A, inermis A. maculosns : A. piewus ~ Aimermis - Mitelich, Miicach, Warburg Mitchell, Warburk = Lichr- Rawson Bradshaw & Ueatwole Rradshaw present study present study f1965h) present study 9nsh) & Shoemaker Main (1968) (1970) (1970) T1966) Eouritie sya” termnerabune CT™ aa,9°> a5" ase 485°C 44,550 465°C Lethal 495°C 49.6°° feMpPeralu re Survival 300 min a B40 min 480 min. 103 min. hI+G.As £59 ar4gzec at 44ec an46e°C —omtins at 46°C EWL VAG meester 158 m2/2/hr O33 ns/sfhr 1.052 0.0913 ar37.sec at a7.s°C at arsec mem! hr ar asec The critical thermal maximum (CTM), de- fincul by Cowles & Bogert (1944) as that Temperuture at which a reptile loses nruscular co-ordination. has heen determined for a oum- her of Australian lizards (Warburg 1965 6; Heatwale 1970). Comparisons between these data are diffi- cult to make because of differences in ex- perimental procedures. Also, the usefulness of this thermal criterion has been criticised because some lizards: after losing muscular co- ordination and passing into a coma, are cap- uble of recovery if held at that temperature or if the femperattre is lowered. Other lizards do not recover after these muscular spasms and die quickly, or within a few haurs- The CTM for A. mectiosas was. determined using only 5 specimens. "The test lizard was placed in a beaker in an even maintained at 48°C. After 15 minutes the temperature was raiscd at the rate of 1°C every 5 minutes, The average CTM for A, inaculasas, derived from these five test animals, is 45.9°C. Two uf these (one male, one female) recovered fully when the temperature was lowered after the lest, The temperature from which there has been no recovery after cessation of muscular spasms. has been recognised as the lethal temperature for this species. The survival times at high temperaiures have been revarded by some authors ys more meaningful criteria) and these have been determined for several Australian agamid lizards (Warburg 1955 a, b: Licht, Dawson & Shoemuker L966; Bradshaw & Main 19468). Por A. mactlosus, a survival time of 6.5 hours at 45°C was recorded, and over this period an 8% loss of body weight occured. Texts curried out at 42°C resulted in death between 22 and 25 hours following a loss of 6.3% of the hody weight TF death yt this Jow level ef hody weight loss Jef, 34-4996 Joss at death for some iguanids (Hall 1922)} were due ta desiccation only, it would indicate a rather low tolerance to desiccation for A. macnlosus and its depen- dence on retreat to the humid region above the salt water-table of the Jake. Further evidence of low desiccation tolerance bas been observed in the vivattum where deaths occurred when the artificial “water-table” was not muintained and sub-surface humidity level dropped. Evaporative water losses haye been deter- mined for 2 number of Australian lizards (Warhure 1965 a,b, 1946; Dawson ef al, 1966: Bradshaw 1970). Attempts to measure evaporative water losses of 4. niaculosus were carried our using test animals either fresh from the field or which had been acclimated to a 24 hour evele involving the attainment of tem- peratures in excess of their maximum voluntary activity temperature. Animals were tested be- tween 1000 and 1500 hours, their most active part of the day. The five animals tested yaried from 8 g ta 14.5 2 in weight (mean 10.5 g), Although the meusured EWE, rate for A. yaculosux varied, probubly in relation to the degree of activity of the test animal, the average value was 1,10 me/e/hre (08-1.5 meg/erhr). Of this total EWL, pulmonary losses contributed 0,83 me/e/hr (0.52=1.15) and 0.27 me/e/hr (0.42-0.29) was due to cutaneous loss, Bradshaw (1970) has found significantly lower cutaneous and pulmonary walter loss in the desert-adapted .4. mermis than in other species of Amphibelurus from more lemperate habitats, His results suggest that the improved water economy of the desert-living specics ix due both to reduction in the metabolic rate and to alterations in the integument. In Table 3 comparison is mide between cutancous and pulmonary water [oss in A. maculoses and A. inermis. The Jaw propertion of total EWL attribu- table to cutaneous loss in the present figures 62 F J. MITCHELL for A, muculosus suggests that the integument may be further modified against evaporative losses. More detailed work is required to accurately define the critical ambient and body tempera. tures, and rates and sites of evaporative loss, in A. maculosux. However, available data do TABLE 3 Rates of eittineous and pulmonary water lossy in A. maculosus and A. inermis A. maculosus A inermis iT 5 6 hody Weight 10.5g 24.1+0.97¢ total RWL 1.10 mg/g/he 1.05£0.0913 mg/g/hr cltaneous 0.27 mg/g/hr 0.452-0.0933 mg/g/hr pulmonary 0.83 mg/g/hr 0.57=0,0778 mg/e/hr c/P ).33 0.80 suggest that its Lemmperalure tolerance is among the highest known for Australian lizards, and that evaporslive Water Josses are among the Jowest recorded, In its natural habiuu, A, ntaculosas, like other heliothermic reptiles, uses a series of be- havioural postures and movements to maintain body temperature within a preferred activity range. This activity range of ftetnperature is higher in the field than the eccritic or preferred temperature selected by the Jizards in a labora- tory temperature gradient. However, except under some conditions imposed by the social hierarchy, the lizards can avoid intolerable heat levels by retreat to the damp sand of the bur- row zone, Subservient mules, kept away from the burrow zone by the dominant tales, are forced to spend long hours on the salt surface with a consequent high level of body heat. Survival under these conditions must indicate the existence of plrysiological capacities to withstand high temperature and to restrict water loss, High body temperature is tolerated passively and water is conserved by lack of evaporative cooling mechanisms. 10. Establishment ond Defence of Territory by the Male, The early emergence, in tute August, of dominant males of the previous season 1% usually preceded by these lizards positioning themselves just below the salt crust where they can more quickly respond ta imcréasing tem- peralures. By mid-September the territories established by these dominant males are under challenge by the younger males which have subsequently emerged. An old mule challenged and displaced by a young male retreats under- ground for the remainder of the breeding sca- son (September to late December). By mid- October the tertitorial situation has become fairly stable, and remains so throughout the breeding season. Apart trom the juveniles (siout-vent length <40 mim), three categories of male can be recognised in the dominance hierarchy, (1) Dominant: lizards which exhibit display behaviour and fight and never retreat from another male. These lizards develop marked breeding coloration with bright orange-yellow ventro-latcral murkings grading to brilliant. reddish-orunge ven- trally with « pale patch mid-ventrally. The reddish-orgnge murkings extend onta the base of the tail and under the thighs. Sub-dominanit: lizards which exhibit dis- play behaviour and which retreat instantly from a dominant mule but will fight to a decision among themselves. Among these lizards a “peck order” is established des- (2) pite their individual territories. These lizards alsn develop good — breeding coloration. Sufservient males: lizatds which do not exhibit display behaviour, and) which re- treat from all other males or rol] over into. submissive posture on their backs if attacked, Only very faint yellow ventre- fateral eMlours ure developed by these lizards. The territorial defence of the dominant males follows a classical pattern. Each tetri- tory is centred upon a look-out site, usually a amufl mound of salt 10-20 cm above the sur- ronnding salt, or a piece of sull-encrusted urifi- wood embedded in the lakc, The area of territories varies about un average of 15 m radius and is, in part, dependent on the virility of the controlling mule. Orientation within their own territory and that adjacent to it fs, at least partly, by sight and the boundary between the tennitory of two dominant males is known ta those two males lo an accuracy of a metre ar so. ‘The forcing of one mile over the boundary immediately precipitates att approach and challenge from the adjacent male, This technique can be used to determine hierarchy patterns in the ficld in arcas where terrilories af dominant males are adjacent, Male TH will ECOLOGY OF AMPHISGLURUS MACULOSUS a flee if forced onto the territory of male I, but will fight (and win) against male Lin bis home territory, The display behaviour of the dominant males invalves a typical push-up movement in which the forelimbs ate flexed and the whole of the forepart of the body moves. A short frog-like leap is followed by two quick push- ups. In challenging another male. the gular pouch is lowered and full threat display follows in which the body is raised high and compressed laterally $0 as to increase apparent size by enlarging the profile during a lateral confrontation (Fig. 12). This alsa displays fully the bright ventro-lateral markings. Usuully the mouth ts opened wide (Fig. 13). This display is usually adequate to deter in- truders [rom entering the territory. When male to male fighting does occur an established pat- terh of events is observed. There is long-range recornitean and challenge at distances of up to 4m. then the commanding dominant closes the distance until a counter challenge is issued ata distance of about 3 m, after which the two males approach each other to a distance of about 0.5 m. There follows up to 10 minutes of bluff behaviour, side stepping, continual facing-up and counter-facing in an effort ta get the tai] into position to lash the oppanent’s head and forelimbs, and the head in a position where it is possible to bite the opponent’s hind legs and buck of the tail (Fig. 13). Head-on encounters also uccur with the opponents’ jaws becoming interlocked in tenacious biting In an cleven minute encounter, the langest ohserved, between males T and I ia the hier archy, three physical clashes occurred. The biting was directed at the hind limbs and each clash was Over in an instant, the attacker being flung vetticully by the momentum of the tunge and the evasive endeavour of the opponent, There may be overlap in the territories estab- lished by the sub-dominant males. While the dominaats remain “on guard” in their terri- tory throughour most ot the day, the sub- dominant males adjust their emergence times so that only one ts active within the territoty at one time. Subservient males adjust their emergence limes to periods when they are less likely to be pursued by the dominant males—in the heat of the day or late in the afternoon. Their level of tension in the presence of the dominant male is reflected in their respiration rate which may be as high as 120 breaths/ minute as com- pared with 35 breaths/minute for the domin- aint. They spend a very limited amount of time on the surface and then avoid recognition by flattening themselves, with head down, against the sult and remaining motionless for long periods. It challenged they immediately turn Over onto their backs in submissive posture. Once ground temperature excecds the threshold the dominant males will emerge at about the same time (10 minutes) each morn- ing independent of light intensity oF temperulure, Heath (1962) records a similur temperature and light-independent emergence in Phrynosante, suggesting the presence of endogenous circadian rhythm. During the breeding season this emergence lime gels carlicr by about 30 minutes each month. Aftce the breeding season emergence becomes rcan- dom and the dominant males generally spend more time underground, At thes time there is an increase in acuvity of the subservient males which spend longer periods active on the sur- face of the lake, There is a lowering of ten- sion between dominants and subservients (re- flected in the fact that respiration rates are simitar for both), and the subservients are Jess inclined to retreat underground or to remain “froze and thereby inconspicuous for Tong periods, Territorality is not actively enforced after the end of December and, while the dominant male spends considerable periods underground, the subservient males embark on an active period ef feeding which involves frequent excursions out over the lake tn search of the unis which, at this fime of year. con- stitute the main food item. In the absence of the dominants, the subservient males may establish territories between existing territorial areas. The dominant males show a renewed burst ol activity in early April, presumably feeding intensively before retiting underground, The dominant males and Jute developing females extend their activity period into May, whereas all others retire into terpor during about the third week of April. The dominant males and the juveniles are the first to emerge and last to retire both daily and annually. Under vivarium conditions, with temperature muintained at 27°C for 12 months, the dominant males and juveniles re- mated active throughout the 12 months. The subservient and sub-dominant mules and the females went into normal torpor despite the maintenance of temperature, These lizards emerged for 1-3 hours every 16-30 days. The 64 bE, J. MITWHELL reason for these arousals from torper ts not known. In the confined conditions of the vivarium, the dominance hierarchy of the “population” is establishecl within about an hour. Hierar- chicul structure can be readily determined by observation of respiratory rutey which range from 30 breaths/ minute in the dominant male to 120 breaths’ minute in the subservient males. Carpenter et al, (1970) have described the display and aggression behaviour of three species of Amphibolurus (A. barbatus, A. retlewlarnys inermis and A. murtcais) aod com- ment on the close similarity between the dis- play patterns of these agamic lizards and the Jeuanidae which haye been more Fully studied (Carpenter 1967). The display action patterns uppear to he sbecies-specific both in the Ignanidae and the Agamidae, The display pat- tenis of A. miaculosus haye not been fully analysed hue the same range of postural changes, ivolving head and forelimbs, des cribed by Carpenter ef al. (1970) have been observed. Brattstrom (1971) discusses the range of postures associaied with social and (thermoregulatory behaviour in A. farhatus. 11, Reproductive Behaviour Vhe adult females of Astphibolurus mutculosus do not emerge until some weeks after the dominant males have established their lerritories. First to emerge at 21"-23°C in mid- Seplember are the older females, followed, through to mid-October, by the younger females. The females establish burrows around the margin of the dominant male territories and do not, at this time, move far from the burrows. A small group of six to-eight burrows, all within a metre or so of one another, usually indicates the presence of a female. At this time of year the burrows are frequently Te- occupied and enlarged whereas later, in the hotter weather, « burrow is seldom used twice. During the first week or so after cmergence the females are pot ready for mating, and adopt two methods to repel the advances of a male. ‘he ficst of these is circumduction, All females of reproductive xize (>45 mm) cir- cumduct with either forelimb in the presence of a male, and the rate of circumduction 1s accelerated if they are approached by the male or come inty competition with the male for food (Fig, 14), Secondly, should circumduc- tion fail as a deterrent, the female twists over on her back and lies immobile. Both these manoeuvres serve to distract the male hy des- troying the “female image” to which he has responded, Most muting activity, and much of the terri- torial fighting, takes place at 34°-36°C, several tlegrees below the temperature (39°C) at which dhe body is maintained by thermerceu- latory behaviour. Consequently during the mating season {October to Deceniher) greatest activity occurs between 0900 ond 1100 hours, While feeding and terjtorial defence take place at 39°C, preoccupation with thermo- Tegulation prevents sexual activiry. The male upprouch to the female usually begins with the male elevating his head to maximum height in order to confirm identifica- tion of sex. He then undertakes a series of energetic head-bobs, followed by one or two “frog-leaps” during his rapid approach to the fernale. A receptive female turns slowly from the oncoming mule und wails to be overtaken. The male approaches the female directly from behind and with his jaws grasps her by a fold of skin just behind the occipital region. Using this nape grasp, the male rolls the female over On her side. With the tail of the male under the tail of the lemale, the cloacae lie ¢lose Logether and a hemipenis is inserted, The pair remain rolled on their sides for the dura- tion of copulation (about 25 seconds) with the body of the female arched hack with fore- limbs clear of the ground (Fig. 15}. Folluwing copulation, the female usually lick in a subservient position, with the head flat on the salt, for 15-20 seconds before moving. During this time the male “frog-leaps” away. Females undertake weak head-nodding during the breeding season, invalving a simple dip and rise of the head, The exact purpose of this is unknown bul, in view of the cryptic coloration, it may possibly serve to muke known their presence ta other lizatds. Following ovulation and ferlilization, 2 number of changes occur in the appearance and behaviour of the females. In u fertilized fernale, ventro-lateral coloration changes fram pearly-white to i bright orange-red, the edges of the lower jaw become orange, and there develop two orange patches between the fore- limbs and two elongate orange patches along the flanks. Also ciccumduction ceases, and more efficient defensive behaviour ia adopted. Upon the approach. of a male, confrontation lakes place with the female raising the head as high as possible and swivelling it around to prevent the male from getting over or past ECOLOGY OF AUPHIKOLURUS MACULOSUS 5 her If this fails, or if the male’s approach is so fapld that this blulE is unlikely ta succeed, the: female rolls over onto her back, frequently well before the male makes physical contact with fer (Fig. 16). Distracted by the changed image the male ustially withdraws several feet, with some head-bobbing. After 15-20 seconds the female vighty herself, inflates the gular pouch and stomach, wnd compresses the bady to display the orange ventro-lateral surfaces and so present the largest possible profile to the inale, The female then adopts a still-legged attitude Which hfts the body clear of the suh- strate and with slow, deliberate steps advances straight towards the mule. She usually passes close in front of him, often forcing him to withdraw a few steps or to transfer his body back on to the hind limbs, lifting the front part of the body to allow the femule to pass close under his snout, After passing the male, the female continues to walk with the stifflegped gait, stopping on each rise in the salt crust to look back at the male over her shoulder. When qhout 6 m away, her pace quickens and finally she relaxes and runs at high speed over the salt lo disappear behind « fold of the salt crust. Io contrast to their timidity early mm the sea- son, femules, once fertilized, become quite aggressive and will attack a male should he compete for food at close quarters. While carrying developing eggs the female emerges at the same time as the dominant niales and spends maximum possible time in basking pos- tures. Perhaps the orange ventro-lyteral coloration of the female at this time increases heat absorption from the substrate. Ventral colour change in the gravid fernale has been reported in the American lizard Crotaphytusr collaris by Fitch (1956) and in Callisanrivs, Copt:oseurus and Holbyookia by Clarke (1965). Evvs are laid 20-25 davs after fertilization, The female digs a distinctive burrow for egg- laying. Normally these lizards merely nose their way under the salt crust and “swim” at a shallow angle through the fine, dry drift sund, down to the damp consolidated substratum. The ¢ge-laying fernale carefully selects a site, usually along the shore-line, of consolidated sand dainp right to the surface. This egedaying burrow is steeply angled (about 45°), extend- ing down 21-25 em, with a distinct chamber at the bottom in which the eggs are deposited. Young females Jay only 2 eggs while older ferales produce 3 or 4, After deposition of the eggs the entrance to the burrow fs filled in again, Observations, both in the ficld and in the laboratory, Sugeest that each fernale digs and fills several egg-laying burrows before she finally deposits the eggs, Whether abandon- ment of these early burrows is due to distur. bance ov whether there is careful sclection of sume particular set of conditions, is not known- The salt content of the shore-line sund is 4-5% and this, apparently, does not impede develop- ment of the eggs. Attempts to hatch eggs under laboratory conditions indicate that maintenance of fairly high humidity during egg development is important. Fenvales fre- quently cmerge from egg-laying in poor con- dition and highly desiccated (Fig, 17). The ventro-lateral colouring fades from orange to yellow to white after deposition of the eggs. Hatching occurs after about 70 days and the hatchlings (SV length 25-30 mm) first appear in January and conlinue to emerge uatil April. 12. Sex Recognition Jn most animals showing marked sexual dichromatizm it ts the male which is more brightly coloured or stronely marked. On this basis il was accepted, in early stages of this study, that large specimens of Amphihelurus maculosus with bright yellow-orange-red ventro- lateral surfaces were male and that this brilliant colouring was a key factor in the sig- nal pattern of male to male sex recognition in territorial behaviour. The sex of tagged lizards was recorded on this basis of presence or absence of ventrolateral coloration, Recapture of marked specimens revealed two stages of development at which colour changes confused this simple interpretation. Firstly, there is the change from pseudo-female to male colour and behaviour at the time the mate reaches the size of an adult female, In some cases, specimens showing weak male coloration were observed to show the usual female responses of circumduction and tonic immobility. On dissection, lizards of this group (all within 43-38 mm SV length). proved. to be male. Recapture records revealed that, up fo S58 mm SV length, the first-year males of A. maculasits show the yellowish ventrolateral markings typical of the female after egg-laying. Lizards of this size (up to adult female size) and coloration are repeatedly identified as fe- male by the dominant males and are driven oul to the margins of the colony by Lhe re- peated unwanted advances of the males, This ob FP, 3. MITCHELL suggests u possible dispersal mechanism within the population, Secondly, some lizards which had been mitially tecorded as female, on subsequent re- capture showed hrilhant ventro-lateral color- ing. Allied with change of colour, there was a change in behaviour with these lizards now counter-challenging an approaching male. This change from nearly-white female to brilliant orange psevdo-male coloration and the change in defensive behaviour and aggression follow- ing ovulation and fertilization have been des- eribed previously. While sexual dichromatism exists, ubserya- lions Auggest that coloration has little if any- thing to do with sex recognition in A- macntosuy, The female undergoes considerable change in intensity of coloration Erom com- plete luck of ventroJtateral coloration through pale yellow to brilliant orange afler miiting, but. is pursued by the dominant males at all stapes in the development of this colour pat- tern, A first-yeal’ male. on the other hand, may show typicul male colouring, with prominent rusty spols oa the shoulders and weak gular pouch stripe and yet be repetedly mistaken for a female, Thus, first-year males, whether they have developed mule coloration or not, are recognised as female within the first-yeor female size ringe of 46-58 mm. In an effort to determine the role played by colour in sex recognition, and to determine whiul colour pattern might act as an innate re- leasing mechanism in territorial display, domimant males in the vivarium were presented with « range of coloured models, sintulating male colorution. None of these elicited any response other than an investigatory lick. The above observations suggest size lo be the basic factor involved in sex recognition and suggest that size judgement is particularly goud, In relation to clevation (most look-out sites in the habitat of the lizards arc no more than 20 em ubove the Jake surface), A. meaculosus shows remarkubly acute vision, Observatians of territorial challenges in the fieldt have indi- cated that these lizards have perception of movement and recognition of posturing at dis- tances of 50 metres. Both laboratory and fiel! observations indi- cple That there is some individual recognition between members of the line hierarchy ¢stab-: lishvd in the vivarium and between males of adjvining (erritories in the field population, TABLE 4 Relationship af size fo uge in Amphiboluruas muaculosus Mean SV length of A. maéulostix (mm ) Female Male Isl year 438 54 2nd year 59 64 3rd year fl 67 4th year 62 70 This significance of size ond accuracy of size perception would also be a u key factor in the effecuveness of the bluff behaviour, Unless the lizards had such an appreciation of size and ils Significance, the act of increasing the wren to view by enlarging the lateral profile would not be effective asa bluff deterrent. 13. Growth Rute and Reproductive Cycle Over the periad of study, 376 body measurements (SV length and tail length) were recorded for marked and Unmarked speci- mens. Based on field recapture of marked speci- mens and vivarium specimens for which age histories were known, niean SY lengths of Amphiboluras maculosus in relation lo uge wre shown in Table 4. The figures represent the mean maximum measurement recorded at the end of the active season for cach year. Mean SV length of hatchlings is 30 mm, It seems likely that A. maculosny dies wt the end of the third breeding season, at 3-34 years, No older specimens have been recovered among the marked population at Lake Eyre, When adult mules emerge at the beginning of the season in September, the testes ate Fully expanded (9x 5 mm). Smear tests show active spermutogenesis trom September through to mid-December and active sperm have been found in the vas deferens in Octoher, Novem- ber and December, In tate Wecember there is a rapid contraction in size of the testes to 6 x 3 mm. No uctive sperm have been found in testes or epididymes from January Lo April. This decline in male fertility coincides with the onset of the period of reduced activity in the males. Between late December and curly March the older miles spend only short periods on the Jake surface and Jonger periods underground, At this time, young mules move back into the territorial areca, subservient miles emerge for lonyer periods and they and the fomales, exhausted after egg-laying. embark on tong hours of feeding, There is litde terri- tori] defence, Ihe dominant males unly weakly ECOLOGY OF AMPFUIBOLURUS MACULOSUS Dominant Mate TABLE 5 Summary of reproductive cycles in Amphiholurus maculosus First yr, male First yr. Firs: yr amt a “Adult female UA) female «R) Female testes defending (with a slight lowering of the gular pouch) a small area immediately around their burrow site. The older males show a more active feeding period through mid-March and April. During this time the testes, together with abdominal fat bodies, expand rapidly prior to the onset of hibernation. Information from recapture of tagged speci- mens, as well as laboratory observations, indi- cates that among the first-year fernales of the population there is a bimodal pattern of ovula- tion, Females hatched during January-February ovulate in November-December. A second series of females, hatching Jate in April, ovu- late in February, Both these groups of females show maturity (as evidenced by ovulation) at 10 months. Of these 10 months, at least 4 winter months (May, June, July and August) are spent in torpor. In the earlier part of the active breeding period (October to Decemiber) the dominant males mate with the adult fe- males. Towards the end of the breeding period the 1st-year females, down to 46 mm SV lengths, are successfully mated by the dominant males, Sperm retention in the female 1s indicated by the decline of male fertility in December and Januars inactive | _ [ a’exien Hatching Ovulation Acilve feeding February Inactive j March Active feecdine Hatching tee April Active feeding it? Testes and far 5 Hatching huadivs expatica ' May June . i Hibernalion | July | Hibernation | Hibernation | Hibernation f Hibernation August First emergence’ H Sentember Establishment of | territory, Spermatogenesis ; : A 4 ka / Ovulation Octaber Spermutngencsis Tdentified as Marine Mating with sdilt feinale, Retreats Cotour females [to edge of terri- change to . | torial uric pseudo-male November Sprermutogenesis Mating with adult | Ovulation fetnales J nt . 7 i aune December Soenmatoxcncsis Returns ta Mating Euetaviag Mating with Tet territorial year females, _ area Contraction of Exe-Jayine the fact that ovulation in the late-hatched fe- males, which had been mated in December, does not acur until February. In March these females lay eggs which hatch in April. The males hatched in January and February are sub-adult (with female coloration and be- haviour) in November-December. Table 45 summarises male and female reproductive cycles of A. maculosus. Acknowledgements The author of this paper would have wished to acknowledge many instances of assistance and helpful discussion during this study. Thanks are due fo a number of colleagues who pave assistance during the field trips, and to the late Elliott Price and the families at Muloorina for their help and hospitality on many occasions. The assistance of Miss Carol Pulley with long-term laboratory observations and records is gratefully acknowledged. Miss Pulley’s careful organisation of the available notes and records of this work has made the present compilation possible. The compiler is extremely grateful to her for this. Thanks are due also to Mr, Michael Tyler and Dr. Michael Smyth for helpful comments on the manuscript. 68 Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig. Fig.’ Fig. Fig. Fig. Fig. 13. 14, 45. 16. 17. F.. J, MITCHELL CAPTIONS TO FIGURES 4-17 . Amphiboaluruy maculosus, showing detail of the head with deeply sunken eye, visor-like eyelid, and absence of visible tympanic membrane. Margin of Lake Eyre, looking north towards Prescott Point at the tip of Sulphur Peninsula, Instruments recording continuous air and sub-surface temperatures are set up in the burrow zone area. The beach is backed by low white sand dunes and to the left the thin distorted crust of the burrow zone merges into the thicker, smoother salt crust of the “wet” salt zone. . View back along the causeway towards Prescott Point (October, 1966), Quadrats were set up along this causeway and movements of tagged lizards were recorded in the area over several years. - Buckled surface of salt crust on Lake Eyre. View towards Prescott Point. . Nesis of the ant. Melophoruy sp., are regularly spaced throngh the “wet” salt zone. The above-surface mounds of these nests are visible here as dark spots (from their shadows) in contrast to the white salt surface. . A. maculosus male against the disturbed base of Mclophorus nest-mound. These mounds are used for basking and shelter and as vantage points by the lizards. . A maculosus, overheated by pursuil, showing panting reaction typical at raised body tempera- tures. Note deep “lens-hood” protection for the eyes. . Salt clods on digils of a forelimb. - Dominant male in full threat display. Body raised and laterally compressed, gular pouch and stomach inflated. Dominant males fighting. Specimen in background shows compressed and raised body, gular pouch lowered, and mouth open for biting. The tails are brought into play to whiplash the head and forelimbs of the opponent. (Dark areas at base of tail are identification marks, ) Circumduction by A. maculosus female, A maculosus in copulation. The male biting and holding the female by skin fold behind the head, A maculosus female (left) showing post-fertilization colour development on lower jaw (the under abdomen is also bright orange) and the typical defensive position. relative to the male on the right. Female, after egg-laying, showing lateral skin flaps under conditions of starvation and dehydra- lion, ECOLOGY OF AMPHIBOLURUS MACULOSUS 69 70 F. J. MITCHELL 7 AMPHIBOLURUS MACULOSUS OF ECOLOGY ee ae ee He MITCHELI es tae ~ fu 2 se, : per ae ECOLOGY OF AMPHIBOLURUS MACULOSUS 73 74 Fk. Lo MITCHELL! = stetre a io a ‘ ‘ t or i SNES. ».4+ nabs > ery i 5 te rah Ete ECOLOGY OF AMPHIBOLURUS MACULOSUS 7s 74 FE, I MITCHELL References BARIHOLGMEW, GA. & Tucker, V. A. (1963 ).— Control of changes in body teniperature. metabolism, and civeulation hy the agamid lizard Amphibelurus barbaty. Physiol. Zool. 3H. 199-218. Bonyrnos, ©. W, (1995) —In “Lake Eyre. South Australia, The Great Flonding of 1949-1950". The Report of the Like Eyre Committee, R- geogr. Soc, Aust. (S. Aust, Branch). (Griffin Press: Adeliide.d Bony ram, C, W. (1L956).—The salt of Lake Eyre —irs oecurence in Madigan Gull and its pos- sible origins. Trans. R. See, 8. Auxt. 79, 66-92, Bonyrnos, ©. W. (1960) —A deeade of watching for waler in Lake byre Proc. 8. Aust. Brel. R_ weour. Soc, Aust, OL, 1-8. Branstiaw, 5. D. 11970).—Seasonal changes in the Water and electrolyte metabolism of Anphi- bularis lizards in the field. Comp. Bioehem, Phyvsith, 46, 689-718. Buapsuaw. 8, D. & Mar. A. Ry (1968),—Be- havieural attitndes and revalutviwoo of tempera- (ure in stnphibaluris lizards. J. Zool, Lond. 154, 193-221, Brarestrom, B. H. (1971).—Social and therme- regulatory behaviour of the Bearded Dragon, Amphibolivus barbatns. Copeut 1971 (3), AB4-497. CARPENTER, ©. C_ (1967),—Aggression and sacial structure in Tguanid lizards. Je W. We Mil- stead, Fa. “Lizard Evology: a synyposium”, pp. 87-105. (Univ, Missouri Press: Columbia. Cvrpestor, ©. C.. Bannan, J. A. & Kimere, B. (1970).—Behaviour putlerns of three species of Amphihelurnis (Aganidac), Copela 1970 (3). 497-505. Crargke, R. P. (1965).—An ethological study: of the Igiianid lizard genera Callivauris, Copla- suuruy and Holhbroukin The Eniporia State Research Studies 13 (4), 1-66. Cowers, R. B.. & Bognrt. CM, (1944).—A pre- liminary siudy of the thermal requirements of desert repriles. Bril(. dim, Mus. nat Hist. 83, 265-296, Dawson, W. RL Sitdietiakien. Vo AL (19664, small 594. Fivcn. HH, S. (1996 ). s “ aw =| EAST LIMB ye FS $| PARNELL *. ‘ SYNFORM /. b . A 50 SUB-AREA IV \ 506 i ; WEST LIMB ie / PARNELL SYNFORM Easterly EAST LIMB 10 . PARNELL SYNFORM P 7 a Westerly Westerly Easterly DIP OF LAYERING Fig. 4. Relative dips of layering and schistosity. = RK. W. KR. RUTLAND that the Sisters fold is of an earlier generation than the Group One Mr. Vulcan antifurm and the associated S, schistosity, and there is clear evidence of minor folding earlier than the schistosity.. Most minor folds in the hinge of The Sisters synform are Group One structures of distinctly Variable mortherly plunge, One excellent ex- ample of earlier minor folding occurs on ihe hinge of u Group One structure, The earlier fold on which the schistosity has been super- posed has a nearly horizental plunge and an east-north-east trend. Conceivably therefore the main Sisters fold is a reclined carlicr struc ture on which the mami schistustty and usso- ciated Group One minor folds have been superposed. Vernon (196%, p. 52) also notes that “small isolated jsoclinal fold hinges in quartzite fxyers can he traced around the hinges of the relatively large folds” at the Sis- ters. Further south in the traverse ESE of the Springs H.S. (sub-area VIIL, Fig, 2) a Further complication occurs with the recognition of two schistosities. The muin schistosity generally dips north-west in the western limb of the Mc. Vulcan antiform. In the north draining valley about two miles east of the Springs H.S., how- evec, both the layering and this schistosity are folded round the hinge of an antiform whieh is therefore Group Two with reference to this schistosity, A new schistosity is locally deve- foped in the Hinge, however, so that with reference to the later schistesity the fold is Group One. Ik is not clear which of the sehstosines should he correlated with the single prominent schistositv immediately to the north. If the earlier schistosity is so correlated (as is fay- Oured by its intensity) then it may be described as 8, and the Jater schistosity can be regarded asa loeul development of S.. Lf, however, the Jater schistosity is correlated with that to the north (as is favoured by their orientatians) then the earlier schistosity must be regarded as one preserved from an euslier period of de- formation, ic, it would be an S,, schistosity. Purther work is needed to determine unequi- yocally whether the major antiformal structure in refiuled to the earlier or the Inter schistosiry but the seoond alternative is here preferred, Further south again in the traverse between Razer Back and Moorkaie the schistosity- luyertny relations indicate the presence of o Grup One synformal structure east of the fai uniform (Fig. 2), West of the Springs H.S., however, layering again dips west more gently than schistosily and the Moorkaje syn- form is therefore regarded ag a relatively xub- sidiary fold on the west limb of the major Mt. Vulcan antiform. It is notable that both Group One and Group Two folds and lineations in this region have northerly plunges (Fig, 3, swb-areas WIT. VITT and EX). Schistosityayering intersections, however. are much more vuriable and may have any plunge within the NE striking zone corresponding to the general allitude of the schistosity. Tt is inferred, therefore, that the Mt. Vulcan antiform as defined, is a Group One structure superposed On tsoclinal folding represented by the Sisters Synform. It is evident from the relations desenbed, however, that this Group One structure could correspond im aye to Group Two structures elsewhere, which fold an carlier schistosity. It cannot be assumed that the antiform is an anticline or that it folds a simple succession of constant Facing, (2) The Maybell areat the Parnell Synform The hinge zone of this structure occurs in sub-area IV in a group of mica schists with quartzite and quarty-rich gneiss interbeds, Both schists und gneisses are commonly garnet- ferwus. The well-developed lavering and schistosity in these rocks has facililated folding which is tighter and of smaller wavelength than in the Mt. Vulcan antiform. The hinge zone is made up of several folds so that the main axial trace is not easily drawn without detailed mapping (Fig. 6). The map suggests that the axial trace has suffered some right-lateral offser on the ENE trending shear zones which cross the area, The diagram of mesoscopic data for this structute (Fig, 3, sub-urea TV) is somewhat diffuse so that a plunge variation from gentle north to gente south can be inferred, At least part of the spread is due to Group Two folds aml these generally plunge to the south. The main fold, however. is clearly a Group One structure and minor Group One folds more commonly plunge to the north (Fig. 3). Bvi- dence along the main hinge line in the northern part of the area for example gives a plunge of 16/020 while dextrul folds on the west side of the gneiss in the south of the area plunge $4°/028. A few hundred yards west of the latter outcrop, however. Group One folds in interbedded qnartzites and schists plunge 30"/ 196, Mineral lineations have occasionally beca observed to plunge north at moderate pngles 83 MAJOR STRUCTURES IN THE WILLYAMA COMPLEX “gale UBDTNA ‘YAR-SIASIS a] Ul sJuawWaye [einjong “¢ “BIy \ we ny SUM1dWO | y $78.4 gee ont ; + A , r T ih abet aif f ra i & 905 7 i Bi ow * F patil ‘4K os a oe a * fer - ‘ 7 w oN See Wee Ail \ _-* : «i ‘, 5? ancy Pe os ci ie ae e / wh ee Sy od leh — 78 eb a ate | WAT Oa ep fe \ os | ¥) 7 =. oy 4 ’ \\\ os, es RS \ fe wy! ‘ rs . ; TL at 2 cab NS ES hs 9 le mL ig o fh Nia se} ‘ : : ("s \ = BT ree SN 5 \e Pdiee ja \ & \ \y wn \ , 3% ‘ Seg . er gp " SONTHdS AHL, er | & Fig. 6. a de¢xtral relationship on a southerly plunge but near the eastern margin of the sub-area _some sinistral minor folds occur, also on a southerly plunge since the layering here dips east more steeply than the. schistosily. This sug- gests the presence of an overturned south plunging antiform-synform pair on the western limb of the main Parnell synform. The axial trace of the Apollyon anticline as mapped by relationship Parnell in the Synform L.Chenoweth and L,Schmidt i f A283 751 7 63 2 eo i A co a he 8 ay. ht V5 BS vss ag —- Layering Lj} Sehistosity 4 8B wn »=ORetrograde faylt zones a a Approximate trace of Parnell Synform Vabtty o ri L 11 1 i | ho OM bites Structural elements in the Maybell area: the Parnell Synform. King & Thomson (1953) runs through this area and further work is required. Also in this sub-area, close to the track cast of Mt. Franks the quartzo-feldspathic sedi- ments show a strong “elongation” Jineation plunging south-east in relatively low angle schistosity. These rocks are also inyaded by abundant pegmatite and they provide a strong structural contrast with the tocks further west, MAJOR STRUCTURES IN ‘THE WILLYAMA COMPLEX Possibly the lineation and the schistosity which is sensibly parallel to layering are preseryed from a deformation episode earlicr than the Parnell synform. In sub-area I there is relatively little peg- matite and the rocks are commonly phylilitic, though some members are rich in andalusite porphyroblasts, around which the schistosity is deflected, The layering again generally dips east more genlly than schistosity but in con- trast to sub-areas IL and IIL the relationship is now generally sinistrul and the plunge of the Group One minor folds is to the north, The Jayering actually trends ubout N-S and the schistosity about 030°. Thus the relationships are still consistent with a position in the western limb of the main Parnell synform but the trend of the layering $7 hus changed and the plunge has changed from southerly to northerly. These changes might be attributed to the presence of a southward clos- ing Group Nought fold between sub-areas I and Jl. No evidence of such a fold has been found and the strong contrast of structural style between the two sub-areas rather suggests the presence of a thrust fault. Nearer to Mt. Franks there is a reversion to a dextral relation between schistosity and layermg and to a southerly plunge since the layering continues to dip east across a nearly vertical schistosity, On ML. Franks itself there is a Jarge dextral fold and crenulation cleavuge is strongly deve- loped. It is apparent, howeyer, that the S; schistosity which has suffered crenulation was itself formed at a high angle to the layering. = N 4 _ - IEE aT (Rad 8 EG /, bS / } i Ff of ( 56 el of of! x t E | y ‘ f f AVR Nae HONKY NE LF INE PI ON TS 7 boa "IC Xe / wa ral la Wt (2 Me 4 \ WY , F| irs Z io ‘ qe 4 oy Near +9 \ \ iF f af 5 / F { a “ is ; 7 ! # \Wese AG Ps Te ) a Tee ps 2} Seat Ph - f ae ft Op / “& Se ot wf i \ { fs a i / LS a ein ut cies Hel f of oe a leg AN. a ( 4) ) / f / i ah oe , y 5 j - Bh as} / 2 Pat AWS ¥ A i (3 f Ved a re - des i A lp aol FY She os, wy \ c a toe é > ae ‘iad by c ~ ¢ Le ¥y, _ a ri we/ t \ fa. aa yf ~~ ey, YA to f § Ma ge ol af \ as { / = Sei)? \Y 7 ee) ‘ Pres ¥ ye | fe so 1 } Metres Milometees pre Broken Hill | =— Road >— «Group I told axis “+ Intersertion of layernny and schistosity oe Layering > #$Groun DT told ents Rh Creriglathen cleavage LI Sriratosiry —+ ~=Mineral broeatien ta} Areas af sa jd poet water Fig. 7. Structural eleinents in the Old Mt. Gipps area. 8s R. Ft is inferred therefore that the main Mt, Franks: structure is essentially a large Group One dextral fold modified by Group Two folds and crenulation cleavage, As noted above, the elucidation of the relationship. of these obser: vations io the interpretation by Anderson (1971) of the Mt. Robe area must awail further work. Conclusions minor folds of Group Nought, Group One and Group Two styles have been recognised and would suggest the presence of three periods of deformation if it is assumed that the schistosity is everywhere of the same age. Some doubt is cast on this assumption by the fact that in some areas (particularly the hinge zones of the major structures) the schistosity is con- sistently steeper than layering and mukes a chs- tinct angle with it while in others (especially in the limbs of the major structures) it 1s nearly parallel to the layering. The Parnell Synform and Mt. Vulcan anti- form are apparently of Group One character since ihe undoubted $, schistosity is roughly congrucnt and forms divergent or reversed fans. Since the schistusity attitude varies sys- tematically according to its position in these folds tt seems probable that the folds and the divergent schistosity, non-parallel to layering, were formed during the same deformation epi- sode, Nevertheless the fact that the layering generally shows « dextral relation to. schistosity in both limbs of the Parnell Synform suggests that the schistosity has been superposed stighly obliquely on the fold, after the initia- tion of buckling. This oblique superposition may be partly responsible for the difference in plunges in the two limbs of the Parnell Syn- form hut there is some evidence that earlier folding is also significant. The dominant dextral relation of layering to schistosity sugycsts that Group One folds related to the schistosity should plunge south- cust in the West limb and north in the -east limb of the Parnell Synform, In fact schistosity-layering mtersections and fold axes (Figs, 3 and 8) show a wide variation in att- tude in a great circle zone striking NNE. This suggesis that the laycring attitude on which the schistosity was.superimposed was variable, pos- sibly due to earlier folding. Moreover, there is not a close correlation between the attitude of Ww. R. RUTLAND ' ——~ 4 | eh ' a ' . “a ," . ' “4 nf ‘ 4 / a» ah Eee / Ao ? «1 7 / os Mn \, / 4 ‘ = / . atte , ‘ al { . ate | . my \ | . Jt ¥ | . i a | = ee { . . i} “ 4 ° \ “ap a4 y ' * Iai 2 Fs i .* 3 ree “4 5 . ‘ - «’ 4 . ‘ “ 2 \ . a . 4 - 7 oy . 2 - 4, , ¢ + % ‘ 4 *s . le 7 a Pe The « Cevp tT tntan Timeations Fig. $ Lower hemisphere equal-area projection of fold axes and lineations for the whole Irunsect. Group One folds and schistosity-laycriny inter- sections, There ts a closer correlation between layering-schistosity intersections and Group Two folds suggesting that the latter have been controlled by the former. Minor folds of Group Nought character which can unequivocally he said to be earlier than the schistosity are rare however. The di- vergen| schistosity inevitably approximates to the axial plune of any eurlicr pearly isoclinal foluls and the distinction can be made only in areas of favourable lithology and exposure’, I. has giready been noted, however, that un carlicr schistosity may be preserved, and the evidence in gneisses of u metumarphic layering tarlicr than the S, schistosity provides con- vincing evidence of an eurlice deformation epi- sode. On the map-scale moreover, the Sisters Yok and some others appear to be isoclinal major structures earlier than the Parnell syn- form and its related schistosity. Since the axial planes of these isoclinal folds are approxi- mately parallel to the limbs of the Parnell syn- form it follows that they were recumbent before the deformation which produced the Parnell synform (Fig, 9), %A good example outside the area under discussion can he seen south-east of the main road, about onc km north-east of the Flying Doctor base, There the schistosily-layering Telationsbip is sinisuwal and congruent Group One minor folds oceur with south-westerly plunges o! about 50". The schis- tosity culs across occasional earlier dextral folds which plunge north-north-east. MAJOR STRUCTURES IN THE WILLYAMA COMPLEX ay cf PARNELL SYNFORM ‘hrust oof deformation Possitie PAbliat Sehistosity (Sy ) cf MT. VULCAN ANTIFORM Axial trace of probable wcarlier Tatds and attitude Of #ariter sohistosity Layering | S7 Fig 9. Diagram to show general form of the Parnell Synform and Mt. Vulcan Antiform and their possible relationship ta major structures of the inferred earlier generation. No attempt is made to show specific early structures which have been postulated. Three major deformation episodes are there- fore inferred: 1, Dy; Formation of tight Group Nought folds (apparently Group One if the later S, schistosity 1s roughly parallel to the axial pline or if 5, is preserved) including the Sisters synform, Original attitude possibly recumbent but now upright with steep plunges, D,: Development of the main folds, the Parnell synform and Mt, Vulcan anitiform together with their associated (S,) schis- tosity. 3, Dy: Formation of relatively minor Group Two folds, plunging south except in hinge urea of Mt. Vulcan antiform. Further work is now in progress on a fur- ther east-west transect, immediately north of Broken Hill. ft is hoped to test the conclusions presented here, to extend knowledge of the Major structures ind to correlate the deforma- tion phases recognised with those established re by other workers (Hobbs 1966; Williams 1967; Anderson 1971). Acknowledgements The mapping, on which this paper is based. was carried out by a group of Honours s{u- dents of the School of Geology, University of Adelaide in May, 1969, under the writer's supervision. The students were Messrs. K. F. Bampton, T. H. Bell, L. M. Chenoweth, D. A, Couzner, T. M. Clifton, N. J. Crase, R, A, rears, D. N. Harley, P. G. Haslett, A, N, Larking, H. Mastins, R. K_ Netzel, P. R. Pierce, L. E. Poole, B, V, L. Rees, P. W, Rooney, B. L. Schmidt, R. E. Williams, A preliminary version of this paper was circulated as Rescarch Report No. 1 of the Centre for Precambrian Research, University of Adelatde, 1969. Financial assistance from the Broken Hill Mining Managers Association is also gratefully acknowledged. References Anpbrerson, D, FE. (1971).—Kink bands and major folds. Broken Hill, Australia. Bull, geal, Soc. Am. 82, 1841-1862. Anprews. E. C. (1922).—The geology of the Broken Hill district. fem. veo! Surv. NSW g. Binns, R. A. (1964).—7Zones of progressive re- gional metamorphism in the Willyama Com- plex, Broken Hill district, New South Wales. J, geal, Sac. Aust, U1 (2), 283-330. Gusrarson, J. K., Burrete, H. C., & Garretry, M. D. (1950), —Geology of the Broken Hill deposit, Broken Hill, N.S.W. Bull. ecol. Soc. Am. 61, 1369-1438. Hoss, B. FE. (1966)—The structural environment of the northern part of the Broken Hil! ore- body. J. geol. Soc. Aust. 13 (2), 315-318. Hoses, B. E., Ransom, D. M., VERNON, R- Hi, & Winteiams, P. PF. (1968).—The Broken Hill Ore Body, Australia: a review of recent work, Miner. Depostta 3, 293-316. 90 R. W. R. RUTLAND Kine, H. F., & THomson, B. P. (1953).—The geology of the Broken Hill district. Jn Geo- logy of Australian Ore Deposits. Prec. Fifth Emp. Min. Metall. Congr., Australia and New Zealand, 1953 1, 533-577. Ramsay, J. G. (1967).—“Folding and Fracturing of Rocks.” (McGraw-Hill.) RuTLAND, R. W. R. (1969),—Relations of struc- tural elements in a transect of the Broken Hill Region. Centre for Precambrian Re- search, University of Adelaide Research Re- port No. 1. Vernon, R. H. (1969).—Archacan or Lower Pro- terozoic rocks. The Willyama Complex, Broken Hill area. Jn G. H. Packham, Ed., “The Geology of New South Wales”. J. geol. Soc, Aust. 16(1), 20-55. WILLIAMS, P. F. (1967).—Structural analysis of the Little Broken Hill area, New South Wales. J. geol. Soc. Aust. 14(2), 317-331. THE SYSTEMATICS OF SOUTH AUSTRALIAN PRECAMBRIAN AND CAMBRIAN STROMATOLITES. PART II BY W. V. PREISsS* Summary PREISS, W. V. (1973).- The systematics of South Australian Precambrian and Cambrian Stromatolites. Part II. Trans. R. Soc. S. Aust. 97(2), 91-125, 31 May, 1973. Five new forms of stromatolites from South Australia (nzeria conjuncta, I. multiplex, Jurusania burrensis, Katavia costata and Kulparia kulparensis) are described. South Australian occurrences of Conophyton garganicum garganicum, Gymnosolen cf. ramsayi and Inzeria cf. tjomusi, previously known from the USSR and elsewhere, are also discussed. THE SYSTEMATICS OF SOUTH AUSTRALIAN PRECAMBRIAN AND CAMBRIAN STROMATOLITES. PART II by W. V. Preiss* Summary Premss, W. V. (1974).—The systematics of South Australian Precambrian and Cambrian Stromatolites. Parl If, Trans. R, Sac, S. Aust. 97(2), 91-125, 31 May. 1973. Five new forins of stromatolites from South Australia Umnzeria conjuncta, I. multiplex, Jurusania burrensis, Kaiavia costatu and Kylparia kulparensis) are described. South Australian cccurrences of Conophyton garganicum gurganieum, Gymnosolen cf. ramsayi and Inzeriw cf. tjomusi, previously known from the USSR and elsewhere, ure also discussed. Introduction “This paper is a continuation of Preiss (1972) in which the principles of stromatolite classifi- cation were outlined and several new forms of stromatolites were described, The glossary ap- pended fo Part I also applics to this paper. Systematics Group CONOPHYTON Masiov Conophyton Maslov 1937. 334, Koralyuk 1963: pl. 5, Fig. 3. Komar, Raaben & Semi- khatov 1965; 27, Kamar 1966: 72, Cloud & Semikhatov 1969: 1037. Bertrand 1968: 170. Walter 1972: 102. Type Form: Conophyton lirietn Maslov, from the Dereynin Suite, Lower Tunguska River, Diagnosis: Non-branching or extremely rarely branching columnar slromatolites with conical laminae, usually thickened und/ear contorted in their erestal parts, Content: C, cylindricunt Maslov; C. pietu- lunt Kirichenko; C. cireulum Korolyuk: C. garganicum Korolyuk; C. mileradoyict Raaben; C. Jitu Maslov; C. baculum Kirichenko; C. gaithitza Krylov; C. ressoti Menchikolf; C. cadilnicus Koralyuk and C, confertum Semikhatov. Conophyton varganicum garganicum Korolyuk (emend.) FIGS. 1. 2a. 9a, 13, 12a Conophyron cf. garganicus (partim), Glaessner, Preiss & Walter 1969: 1056, Material: Eleven specimens from Paratoo, S. Aust. Description Mode of Occurrence: These stromatolites have been found only in a diapiric raft in the Para- too Diapir. The basal portion consists of flat- laniinated stromatolite, passing up into large domal structures up to 1 m diam. (Fig. 11¢). Domes are usually laterally linked, occasion- ally separated by small interspaces, then divid- ing into discrete columns, 1540 cm in diam, with conical laminae, Transverse sections of columns round to oval or lanceolate (Pig. Jib). Columns 1-4 cm apart, with some mas- sive bridges, often slightly bent, with axes non- parallel, diverging at up to 30° (Fig. lla). Some of this divergence may be due to tec- tonic disturbances. The original mode of occur- rence is not clear because of the discontinuous outcrop, it may have been a bioberm or thick biostrome, perhaps. 30 m thick. The only evi- dence ag to the facing of the bed is the upward passage from flat-laminated to conical stroma- tolites, with apices growing upwards, Column Shape: Ficld observation shows that columns are somewhat irregular cylinders, with ragged edges, massive bridges and overhanging laminae. Only one specimen was suitable for reconstruction (Fig. 2a). Columns of round transverse section haye a linear crestal zone, while those of elliptical and lanceolate sections have crestal plunes in the long axis of the ellipse (Fig. 11b), Specimens studied in the laboratory also show both types. * Geological Survey, South Australian Department of Mines, Box 38, Rundle Street P.O., Adelaide 5000. 92 W, V. PREISS ‘The margin structure is very irregular. with numerous large bumps, overhanging peaks and shore cornices. (Pigs, 2a, lta). Bridges vary jn thickness from one Or two to several lens of laminae, Branching: No true branching except actual separation of columns from the domed and flat-laminated base, Rarely a small projection with convex, non conical laminae occurs. on the margin of a column, Lamina Shape: In longitudinal axial sections laminae steeply conical, apical angle generally acute (50-90°) but obtuse angles cecur near the base of the columns, Away from crestal zone, laminae usually straight and parallel in longitudinal section, but in places bent down- wards near the column margins, producing a shupe resembling gnthic arches (Fig. 94), Crestal Zone: All laminae more or Jess thick- ened in crestal zone. Some light laminae greatly thickened. Dark laminae arched up and contorted, often leaving irregular voids filled with sparry dolomite, within the thickened light laminae (Fig, 11f), The erestal line, join- ing apices of successive conicul laminae, is very wavy, with frequent sharp displacements of crests (Fig. aj, The overall shape of crestal zone ts however straight (Fig. 12a); ir corres- ponds mostly to Type HI (after Komar, Raahen & Semikhatovy 1965, p. 23, Fig. 5) with uneven thickenings and sharp lateral dis- placements, but some examples of Type Il (without lateral displacements) occur. In places, laminae are deflexed immediately out- side the crestal zone (Fig. !2h). The diameter of the erestal zone is ken os the width be- tween the limits of thickening of laminae, Out of 33 measurements, 63% Jie between 7 and 9mm, 24% between 5 and 7 mm, and 12% betwecn 9 and 12 mm. Lamination; Very distinctly banded and striated in better preserved specimens, consist- ing of straight, parallel, smooth, very thin laminae, either very continueus, or formed by chains of elongated lenses, aligned in definite layers (Figs. Tle, 11f), Two types of primary laminae occur: light { L,} and dark (L.). In some specimens 1. layers grouped inte fairly Uistinct macrolaminae, in Which light laminae are thin and subordinate, separated by layers of predominantly L,; iype (Fig. 11f), The ap- pearance of macrolaminae has been eNxag- weraled by the preferential recrystallizatinn of light laminae. L, taminae relatively pure and transparent, mostly 0.08—-0.1 mm thick, gen- erally of very constant thickness from the else of the crestal zone to the column margin, never lensing out. They are internally homogenous. composed of xenolupic. almost equigranular dolomite, of grain size from O.1H—-0,03 mm. Many grains slightly incquidimensional. Occa- sional lenticular spay-filled cavities have dark laminae draped arvund them Fig. lle), L. laminae darker, much fess transparent and samewhal finer grained than L, laminae, the Fine crystals stained by 3 pale brownish. pos- sibly organic coloration (Fig. 1le). Mast dark laminae 0.02-0,10 mm thick, ont os continuous as L, laminae, frequently splitting into series of lenses, 0.2-1.0 mm Tong, and 0.1—1.0 mm apart, aligned parallel and separated hy pale laminae. Some dark laminae ure continuous for several cin; some have slight, rounded, lenticu- jar swellings, These, as well as the lenses, may be blunt ended, rounded, or pointed, Rarcly, they contain significant swellings, the under- fying ynd overlying jaminae heing draped around them. Relatively large (0.52.0 mm) neduies, within.a pale lamina (eg Fig. Ie) are probably detrital carbonate grains, 1... Ia- minac composed of equidimensional. equigra- ular, Xenntopic dolomite, of grain size 0,006— 0.015 mm. Boundartes of L, and L, laminae distinct and smooth, but slight recrystallization has made them a little diffuse in plages. Mac- rolaminac, consisting of sets of Ly laminae. very prominent in some specimens, are U.4—- 1th mm thick, composed of 5-10 Ly-L. Ia- mination pairs, bounded by predominantly light macrolaminae (.2-0.5 mm thick. often spurry and recrystallized (Fig. 11f), Statistical Study; Numerous measurements were made on six large thin sections, of the following parameters: (1) thickness of light laminae I,; (2) thickness of dark laminae L..; (3) ratio of thicknesses of adjacent dark and light laminae La/L, and (4) coeficient of thickening. i.e ratio of thickness of a lamina in crestal zone, to thickness of same lamina outside crestal zone. The distribution of thicknesses ef Jarninae L, and L., were plotted graphically for thick- ness Intervals of 0.02 oun; the [requencies of intervals were plotted against the mid-point of each interval, for the six specimens (Fig. 1b to g). A comparison of the six graphs for each lamination type shows some variation between specimons, especially for L. laminac, which is interpreted as being due to the difficulty of distinguishing single datk laminae and the thinner macrolaminge in same specimens, This difficuity is increased with rreater recrystalliza- lion, so that one would expect the more re- SOUTH AUSTRALIAN STROMATOLITES IL 93 Fig. 405 a0 3277 § 43) mah 7 | n-2F vy 1740 sod -= 68 ay ay an i s6 specimen: Oa i * G, » of 4t)- i Figs b to h4Lt % 30- \ and | : ih Ug oe _ \ 20- i : 4) {' | op ‘oft Aad “be A AN | Voy 5, {dee odd arar way ‘i i Wise Oo; 27 9% D4 WL 2 oF OF OF & iT mm nmin b c d Ye a f g 40 All specupent Couebned 504 7 Oan Russia), Comoph efor ag Baw Austecrlie Caanepaliyten Bergen iin S.A speciners, MeL CHL SUPCNCE 50) utZ4g 7 Sav reer 7 n=510 “0 20 Russion € arp om Wy) Rargiii ay “W a ao Ben yunlinider pon Toe 3 ‘ BF 0 : Q.4 0 "7 2 4 h las i South Ausira‘ia Conopi\ynn i Russian Conair 13 Laren noun MeN Be UR? 1 we ee Barra uy SURAT t | Margin of i De q ., fated 7 44) SA. specimers; 757 4 Margir of [jatd S.A. Department of Mines 1. Diagnostic characters of Canophytan: (a)—The traces of the crestal lines of two specimens (S214 at left and $532 at right) drawn from thin section (x1/3); {b) to (g)—Frequency distributions of thicknesses of light Jaminae Li and dark laminae Le» for 6 separate speci- mens; (h)—Pooled frequency distributions of lamina thicknesses for all six specimens, com- pared with data for Russian conophytons; (i)—Frequency distribution of the ratio of thick- nesses of adjacent dark and light laminae (La/Li), pooled for all specimens, compared with data for Russian conophytons; (j)—Frequency distribution of the coefficient of thickening of laminae in the crestal zone. compared with Russian conophytons; (k)—Comparison of contour diagrams of the frequency distributions of dark and light laminae (contoured in num- bers of readings), 93 W. V. PREISS crystallized specimens to have proportionately more numerous thicker Jaminae (actually thin macralaminae), Le. the mean thickness should be higher than for less recrystallized ones. The following table Compares meun thickness (in mm) af L, and Lo with degree of recrystalli- zation observed: L. means have much ureater spread about the total mean then L,, and the highest means of L. correspond to the most recrystallized specimens. Degree of Specimen Reerystal- number L, méan La imean lization S214 0.128 0.073 Well preserved $213 0.107 0.066 Slight S278 0.145 0.065 Slight S277 OAL 0.084 Sticht §32 O15 0.089 Strong $43) D.DST 0.134 Siraug Total inealh = D6 0,085 The data for the six specimens were com- hined, replotted, and compared with the dis- iibution curve of the Russian Conaphyior gargenicum garganicun. (Fig, Thy. While the Lo curves are very stnilary L, has a higher mode in the South Australian form (0,08 to 1.10 mm), with asceondury peak tn the mter- val 0.04 to 0.06 mm, which characterized the Russian form, To some vxtent. the bimodality ig due te errars of mevsurement arising from the judgement ul lamina thickness sehilive to the scale of the graduated cyepiver, and to the Presence of thinner macrolaminse ws discussed above, Rate Lyth,y for Adjacent Laminac; Results from all six specimens were pooled and plotted in intervals of 0.25. Fhe graph compares very closely with that of the Russian form (Pig. 11), The dain may also be represented in the form nf « eoutoured frequency divgram of LL. avainst Ly. The shape and position of the maximum are compared with those of con- toured Russian plots; they diller only in that the South Australian form has a displaced seoandary peak at L, = 0.08 ta 0.10 mm, L., = 4K 1 0.10 mm (Fig. 1k). Coefficient of Thickening: Randomly selected light andl dark laminue, and macroluminae. were measured outside the crestal zone th), then traced into the crestal vone and remen- sured (H), H/h was plotted at intervals of 0.5, In a total of 52 measurements, the medal value of Hh is the interval 2.0 to 2.5 (26.9% } while only 15.5% exceed 3.5, and none less than 1.0 occur (Fig. Ij), Inierspaces; Interspave = Aillings — betweeir colunms are strongly altered, consisting of homogencous recrystallized Uolomite Seme is of grumous texture, composed of xenotopic equidimensional (0.005-0.01 mm) grains, forming patches 0.05-0.10 mm in diam., set un a §parry matrix of grain size 0.1-0.3 mm. The only observed remnants of primary structure are possible smull intraclasts in one specimen. Secondary Alteration; Fracturing of laminae is restricted almost entirely to the crestul zones of some specimens and marginal zones ol others. Portions of the crestal zone are more or less breccated and recemented in place (Fig tid). Contertion frequently occurs within the crestal zane, Immediately outside i, laminae wre deflesed: this and the brecciution ate effects prubably due to compaction during burial, The breeeiation of macroluminac into cleanly broken fragments several imillimetres long suggests that the carbanate was already lithified during the deformation (Fig. 11d). Im places, on the column margins, Jaminae truncate underlying laminae. Whether this is due to peneconiemporuneous crosion or ta sliding of the overlying Jaminue during con- paction could not be determined, but associa- led brecciation around the colunm margin sugeests the latter possibility. No overfolds or diapirie structures as in Conoplyron gargani- cum australe Walter (1972) were observed, supporting the idea that columns were lithifted soon after growth. Columns and interspaces consist entirely of dolomite. ‘The preservation of very fine lamina- tion suggests that dolomitizuliun was probably penecontempoerancous, All laminae are more or less recrystallized, the dark laminac are coarser and more transparent that ty the Rus- sian or Western Australian forms. Recrystal- lization may be due to the lew grade regional melamorphism which has wffecicd the Mt, Lofty-Olary Are. Pale laminae between dark mucrolaminue are preferentialhy recrystallized, emphasizing the distinctness of the macro- laminue, These recrystallized lansinwe consist of sparry. hypidiviopic 19 xenotepic incqui- uniqular dolomite, of grain size UA2-0.10 mm. The most recrystallized specimen is a fine marble. in which dark macroluminac, approxt- mutely 1 mm thick, contain no preserved in- ternal lamimac. and consist of xenotopic equi- dimensional curhonate with interlohbate crystal boundaries, of grain sizes 0.02-0.05 mm. The grain. size uf the light laminae is (450.10 min, und in places much coarser, One speci- Men is extensively sillcthed. Silicification pust- SOUTH AUSTRALIAN STROMATOLILES I! 95 dates the prowth of the whole column, and may be related to tectonics and diapiric em- placement rather thun to sedimentation, Silica consists of xehotopic quartz aggregates, of grain size 0.05-0,10 mm, in places containing small dolomite rthombs. Portions are com- pletely redolomitized, Comparisons: Fhe conical Jamination with thickened crestal zone, and the absence of branching dis- ainguish this stromatolite from all groups ex- cepl Conephyron. Tt diflers from most cono- phytons in that the columns are not always parallel, hue theif original growth orientation is not clear. due to structural disturbance. On microstructural features, it falls into the Carp- plvios garvanicwn subgroup (Conophyion gosanicum, C. miloradovicl, C. guuhitza, and perhaps, ©. /aseliicuna Walter), The closely allied C, miloradovict has more irregular and lenueculur laminae. ©. basakicum Walter also has very thin smooth continuous laminae, but lacks (he distinctive Types Tt & LIL erestal zone. The absence of numerous knotted lenses and sharp swellings distinguishes it from the variecly Co wirganicun nerdiciun:. On these feutures it was assigned to Conophyieit cf. garganicus by Glaessner er al. (1969). The statistical study confirms the identifica- tion as Cy garganicum garganicum, and distin- guishes it clearly from C, gareanicion australe Walter und C. earganicum nordicum, The modes of thicknesses 1, and Ly. most closely resemble C, gurganicum garganicum, especially Ly (mode at 0,04 to 0,06 mm), while most other conophytens have modes at mugh higher values, C. garganicum nordicum has a modal value of L, at O10 mm, and C. gargeretnt ausirele Walter at about 0.08 ram. The ratio L/L, ts the most distinctive character for Conophyion garganicunt garganieuin. The modal value is the interval 0.50 to 0.75, which fulls within the broader peak of the Russian form (0.50 to 1.00), but distinguishes it from C. garganicum nordicum Komat, Raaben & Semikhatov (mode 2.00) and from C. gur- gunicum australe Walter (1.0 10 1.5), The co- efficient of thickening is less distinciive: the mode at 2,0 to 2.5 does not distinguish C. gar- gonicum garganicupr, C, miiloradovic? and C. eviindricum but excludes C, garganicui nor- dicum and probably C. g. atesrrele. Distribution: Lower Subsuite of the Yusmas- takh Suite of the west and east slopes of the Anabar Massif; the Kyutingdin, Arymas and Webengdin Suites af the Olenek Uplift; the Gonam Suite of the Uchur-Maya Region, Ust’-sukharin Suite of Western Priver- khoyan'ye, Mongoshiit Suite of the south- eust part of the Eastern Sayan, Bul'bukhtin Suite of the Baikalo-Patom Mountains, Sat- kin Suite af the Southern Urals: in pre-upper Burra Group sediments, Paratog Diapir, S. Aust. Age: Early and Middle Riphean: in S. Aust, itas assumed to he early Adclaidcan- Group GYMNOSOLEN Steinmann Gynineselen Steinmann 1911: $8 Semi- khatov 1962, 219. Krylov 1963: R4, Kamar 1966: 88. Krylov 1967; 346, Raaben 1969; 73 {in parti. Glacssner, Preiss & Walter 1969; LOST. Type Fernt. Gyinitesalen eanisoyi Stein- mann, from the Dolomitic Suite of Kanin Peninsula; also widespread in the Southern Urals, the Polyudey Mountuins, Kildin Island, and Tien-Shan, USSR. Diagnosis: Smooth to gently bumpy, swelling amd constricting, Walled columns with frequent, >-patallcl, often multiple branching, less fre- quently slightly divergent branching, Contear: Grrinesolen camsayi Steinmunn; G. levis Krylov; G. furcunts Komur: G. altus Semikhatovy, "“G confragesus” (in part) Semikhatoy and G, asyminetricus Raaben, Rauben (1969) has included part of the group Minjaria Krylov in Gymno- salen, chiefly on the basis of microstruc- tutal similarity, but Krylov (1963) has clearly distinguished Minjaria from Gym- eesoler by its regular, subcylindrical shape of columns, of constant diameter, and selatively rare and simple branching. Ape: Late Riphean, Gymnosolen cf. ramsayi Sicinmann FIGS, 2b-z, 3a-c, 9b, 10b, 12b,c, 134 Gyninesolen sp, Glaessnet, Preiss & Walter, 1969: 1057. Material: Five spegimens from nears Wilsan Description Mode af Occurrence: All specimens ate bould- ers from conglomerate and breccia bedks within the Tapley Hill Formation on the flank of a small diapir, Only one specimen shows com- pletely separate, discrete, vertical columns, and is interpreted to have been derived from the central portion of a bioherm (Fig, 13a}, OF two specitens showing much coalescing and bridging. ome alsa has markedly inclined columns (Kip. 12c). These ate considered to 96 W. V. PREISS represent the marginal portions of biohernis. The provenance of the boulders has not been determined. Column Shape and Arrangement, Columns straight lo gently. curved, erect, 1-5 em diam., with gentle swellings and constrictions (Fig. 2b-g). Transverse sections generally circular to oval, but lobate and rounded-polygonal at branches (c.g. Fig. 3a). Length of columns hetween branches 5-20 cm. Sone columns short (only 2-5 cm long), with rounded or pointed terminations (Fig. 2c.e). Colunins pre- sumed to be marginal in bioherms are inclined (as inferred Irom the asymmetry of Jaminac and occasional interspace Jumination). “lhe gross morphology of marginal colunins differs only in their frequent coalescing und bridging. und narrow interspaces (Fig. 3b). One speci- men with appurently erect columns is markedly humpy (Fig, 2d). Branching: Slightly divergent to @- or. most commonly, y-parallel. The column expands SA. Déeparrmenr af Mines Fig. 2. (a)—Conophyton garganicum garganicum, from dolomite raft in Paratoa Diapir. Part of a farge column illustrating margin structure. $528: (b) to (g)—Gyrnasalen cf, ramsayi, from boulders in a conglomerate in the Tapley Hill Formation, near Wilson; (h), {c), (e), GF). (g)—Vertical columns interpreted to be derived from a binherm centre. S388: (d)—Poorly presetyed vertical columns. $390, SOUTH AUSTRALIAN STROMATOLITES "? rapidly, then branches suddenly into two, three or four columns, some branches lerminaling as pointed projections. Even in the disercte specimens, adjacent columns muy vecusionally coilesce. The inclined-column specimens branch similarly, hut widening of a columo before branching js more marked. In these specimens adjacent hranches either are [re- quently linked by massive bridges, or coulesce Margin Stevervre: The surface of columns beurs low, rounded bumps, 1 to 2 cm wide. with a reliet of « few millimetres, Short, trans- verse Ur inclined tihs ure exceptional, Mostly it is covered by a wall, up to 3 mm thick, com» pasd af from one or two to ten laminac (Pig. 12h. cb. Generally, the marginal zone of columns is recrystullized, but in places, la- minue bend down near the column margin and extend parallel to it [nr up to 2 em. Leven where wall reerystallized. outer lamina sharp, well preserved, In places, an tnlaminated sel- vupe, up to 0.5 mm thick. lines the column surface. This post-chites the wall formation, and pre-dates the interspace sediment. In the dixerete column specimen. bridges rare: ocesn- sionally where two columns are closely spaced, afew laminae may bridge ucross. Rarely, over- hanging peaks occur: especially iF draped over gn adjacent intractast: some columns arise from laminae grown over intraclasts. Columns in the inferred marginal specimens purtly un- walled: Jaminae thin and wedge out, forming a amuoth murgin, but do not-extend over il. Lusaina Shape: Varies within broad limits. Gently convex laminae most frequent. varving in sectiod from rectangular to hemispherical, Frequently, laminae develup two oor more crests pror to branching, but in some cases, incipient branches are immuuately bridped aver. und growth of the original coJumn re- sumed (eg. the column on the right of the photovraph in Fig. 12b). Different lamina shupes. occur close together in w column, ie. degree ol inheritance of shape is low. Fig. 96 illustrates commonly occurring shapes. OF li- minye measured, 694% have h/d Tatio between 0.2 and 6,6, the mode (26%) being the inter- vil helween 0.2 and 0.3 (Rig. 10b), (In deter- mining lamina shape, the poorly visible, down- turned marginal portions of Jaminac in the will had to be excluded). Laminae mostly slightly wavy, with wavelength 2 or 3. mm, and amplitude 0.2-0.5 mm. Micrasructure: Micrositucture extensively re- ervstallized. Where alteration minimal, alter- uating light and dark laminue of greatly vaty- ing thickness form w distiner streaky miero- structure ¢Fig. |2b). Lighr Jominue are l— 0.5 mm thick Occasional thicker livht laninae (up to | mm) may actually be peervstallized macrolumingae, Light laminae are ¢ontinious ucross the coluron. but thin in the wall zone Very rarely, they are ceuticated hy micro- unconformitivs. They are wrinkled and wavy, corresponding to irregularities in the Wark ta- mite. und consist of sparry, cquidimensional. xenotopic to hypidiotopic calcite, of grain sive UAH-O.0S fom. Trregular patches, approsi- mately 0,05 mm diam, are stuned With a pate brownish (organic?) pigment. Dark lena are 0,050.3 mim thick, hut pinch und swell rapidly along their length. In many places, they are lenticular, consisting of contiguous lenses or nodules 0.1-O.5 mm fang. Usually dart laminae persist ucrass the column, but occa- sionally Jens gut completely. so thit adjacent light laminae merge, The clirk laminae which ure thickest in their crests. consist of brown pigmented xXenotopic, cauidimensional calcite, of wrain sree O.005-U.0ES mim. In places, dark Jaminac limonitic. In arcas of more pervasive recrystallization, prumous textures ie deve- loped in Which clotty remnants of dark Liminae are set in a matrix Of sparry hypihiotopic cal- cite. Poorly differentiated macrolaminue, 0.5- 200 mm thick, consisting of up lo & light dark Jamination pairs, occur in many purts of columns, The internal structure of these 1s often not preserved, resulting in more or less homogeneous thick dark lammae with wavy, sharp, upper surfaces. /nterspaces 2 mm—5S.em wide: where colunms more widely spaced, interspaces Filled with silty intrami¢rite. Intfachiuts are flat pebbles [5-3 em long (Figs, 12b, c; 134, suhrounded, vari ously oriented. und foosely packed (matrix supported), Many stand vertically in the inter spice. Some intruclasts are curved, suggestive of a mud-cracked origin, The matrix consists. of broadly laminated silty, recrystallized lime mud) fine Jaminaé, 2-5 mm thick, consist of yenolopic calcite of grain size 0,003-0,01 mim, while coarse faminac, of about the same thick- ness, consist of hypictotapie 0.03-0.05 mm frain size calcite, with much subangutar quartz, sill, Laminations of the interspace sediment ubut against the column walls, having accu- mulated after the development of significant relief of columns, Secondary Alrerution: laminae are extensivety altered especiully ut the marginal wall zone. In places the lamination is completely disrupted OB Ww. V. PREISS ufound centres of reerystallization, but cam- monly faint lamination or sows of dark clots ure preserved, to indicate the presence of ori- ginully continuous dark laminae im the wall vone, The outer few millimetres of columns are ocommunly recrystallized to career, twinned hypidiotopic calcite, of grain size up to 0.3 mm with inclusions of dark lamination relics, In places, am acicular texture is deve- loped in the wall zone, perpendicular to the column murgin. The central parts of columns ure less affected, but even here, laminuc ure commonly reduced ta dark clots in a sparry culetre matrix. Dolomitization of both inter- space and columns iy found in some specimens, where anhedral to subhedral rbombs of dolo- mite, 0.02-0.06 mim in grain size, are scat- tered more or less uniformly throughout a re- crystallized sparry calcite mosaic, Frequently, lenses of coarsely crystalline, clear calcite occur within the lamination. Coarsely sparry patches, cutting gcross all earlier structures, are probably infillings of solution cavities, since they are closely associated with discordant stylolites. Stylolites are rather rare, and of two génerations, The first are concordant with la- Minae, and contain concentrations of limonite. These are cut by major calcite veins, which in turn are offset by the discordant stylolites men- tioned above. Comparisons The stromatalites ure assigned to Gynima- salen on the basix of their column shape, frequent y-parallel and slightly divergent branching, and wall, In overall column shape an Llype of branching, presence of pointed projections, shape of laminae and micrestruc- ture, (he South Australian form closely re- sembles the type G, raniwayi. Slight differences include unwalled patches. of columns, occa- sional peaks and hridges, and in places it slightly bompier margin structure, G. cf, ravn- sayi as distinguished from G_ furcatis by the absence of markedly y-parallel, multiple branching and by the presence of pointed pro- jections, and from G. levis by its more widely spaced, Icss markedly bumpy columns, G. wits Semikhatov has apparently been affected hy uw strong cleavage, and its columns are slightly deformed, making comparisons difficult, but it appears to have a more continuous, banded lamination. G. aywinmetricus Raaben has thin- ner, smoother laminae thin G. ramsayi. G. confragoxus Semikhutov has in part (specimens from the Shorikhin Suite) deen reassigned by Raaben (1969) to Inzeria Ul. confraeosa); ese specimens are distinguished from G ranisayl by their irregular columns, interrupted will and more frequent peaky and cornices. Semikhatoy's specimens from the Dashkin Suste, now considered as Vendian (Krylov i Rozanoy er af. 1969, p. 215), have much smaller, bumpier columns than G. retmuseeyi. Distribution; Sub-Inzer Beds of the Katay Suite und Minjar Suite of the Karatau Series of the Southern Urals: Niz’ven Suite of the Polyudov Mountains: Carbonate Beds of the Metamorphic Series of the Kunin Peninsula: Kil'din Series of Kil'din Island; possihly the Spatagmites af Norway; Bystrin Suire of Southern Timan; Chatkaragai Suite af ‘Ten- Shan: as clasts in Tapley Hill Formation. & km E of Wilson, southern Flinders Runes. S$, Aust. Age: Late Riphean, in S. Aust,, not younger than the Tapley Hill Formation. Group INZERIA Krylov Mngeria Kryloy 1963: 71. Krylov 1967; 29. Cloud & Semikhatov 1969; 1042. Ravben 1969: 77, Glaessner, Preiss & Walter 1969: 1057. Type Form: Inzerid tianusi Krylov, from the Katuv Suite of the southern Urals, and the Demin Suite of the Polyuday Mountains, USSR, Diagnosis: Subparalicl, usually wnwalled, sub- cylindncal, ribbed columns, frequently with niches containimg projections Branching mostly a- to @-parallel to slightly divergent. rarely y-parallel or markedly divergent. Conn: Lf. gomasi Krylov, £, toctagnlli Krylov, f. intia Walter, and probably /, djejimi Riaben and fF, ayfryslandica Raaben, 4 (Minjarvia) nimbifera Semi- khatov may he included, but Raaben {1969u) has placed at in synonymy with i. fjomusi, and has partly reassigned Gynmosolen canfrayosus —Semikhatov ta Snzeria (L eonfragoxa), Raaben haus, however, considerahly broadencd the con- cept of J/rseria, placing lille importance on Krylev’s (1963) critema of ribbed columns with niche-projectiony, On this basis, Aldania Kryloy (ia Rozanov e¢¢ ol, 1969) could perhaps be better included in fnzeria. Descriptions of 2. macula, 0. varinsata, J, sevintedr and J. chunitbergiva Golovanov were unavailable, but Raahen’s (1969, Fig. 2L) illustration of frzerie nrteuld docs not resemble any other des- eribed J/nzeria. The new S. Alist, forms are I, multiplex und |, conjpimera, SOUTH AUSTRALIAN STROMATOLITES iL ed Age and Distribution: \ate Riphean, wide- spread in the USSR: Bellon Springs. Forma- tion. Central Aust.; Brighton Limestone and Wundowie Limestone, S, Aust; Hinde Dolo- mite. and doubtfully, Dook Creek Forma- lun, NT, Inzeria cf. tjomusi Krylov FIGS, 3h. 2, tieg, |3b- Material: Three specimens from Burr Well. Description Made of Occurrence: “Vhe stromatolites form a lenticular bed, interbedded in green shales, and consist of fottr or five contiguous gently damed bjioherms (Fig, (3c), 2-+ m diam, with a inuximum thickness of about $ mi. Toe wirds the west, the bed thins and lenses nut grsdually; in the easterly extension, columiar stromatolites give way to flat-laminated lime- stone. The lower partion of a domed bioherm consists of Hat-laminuted stromatolitic lime- slone. or contiguous, very broad cummuly (part of which are seen in Fig. 13d). up to 20 em thick; overlying this (hut never seen in sedi- mentary contuct with it), is a zonc, up to 20 em thick, of discrete, verticul, subcylindrical eolurons, 2-10 em Wide, The base of these columms is an intensely stylolitic zone, in which aw thickness of up to several centimetres has been removed by solution (Figs. 13b, d). At the maruins uf bioherms, the columns become inregular and slightly inclined from’ vertical. Columns jre bridped over hy a thin, poorly exposed zone of flat-laminated stromatolites. Column Stupe and Arrangenenrs; Columns short, subeylindrical, with some swellings and constrictions, of diameter 2-10 cm (Figs, 3f. 2. 4a-g), henght 10-20 cnt (the whole thickness of the columnar zone}, Transverse sections round, rounded polygonal or slightly lobate. Columns have vertical, straight axes in the central parts. of bioherms, hut hecome irregular at the edges. Branching into discrete new columns rare, per- haps due to the small thickness of the bed. Niche-projections very frequent; they are short, narrow, usually rounded, sonelimes xlighthy elongated, set into niches in the side of the tain column, which, most commonly. resumes its former diameter at the top of the niche 4Figs. 13b, e: du, d, & g). Occasionally auja- cent columns coalesce, Margin Structure; Due to strong recrystiliza- ton of columns the margin structure is ob- secure. Laminue upproach the margin al u high angle. and are not defiecxed at their cdges; columns always unwalled. Lateral surface of columns with numerous short transverse vibs, up to 2 cm long, occysinnyl overhanging la- ininue and peaks. Th places, adjucent columns linked by bridges up to 5 mm thick, Luminae Shape: Always genlly conver, vary- ing in shape from continueusly curved domes la very low, obtuse cones. as illustewted in Fig. 9c. Lamina shape inherited from underlying Jaminae. without fapid chynves in convexity. Ratios of h/d usvally low; 91% of laminae huve h/d between 0.7 to 0.4 (Pig. 10e). Fine- seule structure of laminae smooth to gently wrinkled. Microstructure: Strongly recrystallized through- out columns, but in places the gross indistinctly banded structure of laminae ts moderately well preserved (Fig, 13e). Relatively thicker light Jaminaé alternate with thinner datk laminae hut recrystallization has in places obliterated the distinction. All laminue have diffuse baun- daties, Light laminae 0.2-2.5 mm thick, com- monty significantly thicker al their crests than their edges. especially in the obtusely-conical laminae. ‘They consist of @ sparry, equigtanu- Jar, hypidiotopic mosaic of calcite, of grain size OES—O.02 mm, with ingluded small, irre gular patches of darker pigmentation. Derk laminae githee smooth or finely wrinkted (largely due to embayment by recrystallized adjacent light laminae), thickness 0,2-1.0 mm, generally thinner than adjacent laminue. Oeca- sional thinner dark laminae are lenticular, but whether this feature is primury or due to Te- erystallization is unresolved, Like the light In- minae, they are slightly thickened in eheir crests. Dark laminae consist of xenotopic, slightly inequigranular calcite, grain size 0.005- 0.09 mm, stained with a pale brownish pig- ment. Interspaces filled with homogeneous recrystal- lized lime mud, with occasional intraclasts, Culcite xenotopic to hypidiotopic, grain size 0,01-0.03 mm, contains about 5% angular quartz silt, Quariz grains corroded by recrys- tallized calcite. Occasional flat intraclasts up to 1 cm long, with diffuse boundaries, in parts of interspaces, recrystallized to sparry calcite mosaic, prain size 0.02-0.03 mm- Secondary Alteration: The whole reck is per- vasively altered, While columns are pale grey, tunsparent in thin section (Fig, 3c). the dark laminae perhaps tinted with arganic milter, iterspaces are pale buff probably due to the presence of small amounts of limonile, Neither columns nor interspaces are dolomitized, The 100 W. V. PREESS S.A DérartmaAns of mines FIG. 3 SOUTH AUSTRALIAN STROMATOLITES UI IU} boundary between interspace and column is always diffuse, obliterated by recrystullization in both, This reduces the reliability of the re- constructions. Highly irregular styloliles with large Jubes sepatale the basal laminated sedi- ment from the discrete columns, with a gone up to 5 cm thick of intense brecciation and late-sisge infilling of fractures by coarsely ervstalline calcite. Possible remnants of the lower portions of columns, highly enriched in limonite, are sometimes preserved between cross-cutting stylolites (Fig. 13e), Large sub- aphericul nodules, up to 3 cm diam., of coarsely crystalline culcite are very commun in the litnestone at this locality. mostly located withm columns, Twinned calcite crystals in these highly elongated, 1-3 mm wide, up to 3 om long, vertical or radially arranged. Mast crystals terminated upwards; their acute tere minations project into the laminated limestone of columns, The major cross-cutting stylolites post-date the coarsely crystalline nodules. Qver large areas, columns are completely tecrystal- lized so that lamination is partly or totally ebli- terated, Such areas consist of xenotepic, to hypidiolopie mosaic calcite, gtain size up to OS mm. Where rtecrystallization incomplete, regular fragments of disvapted dark laminae surrounded by sparry, recrystallized mosaic calcite. Caniparisons The presence of ribbed columns with nu- merous niche-projections places the stromato- -lites in the group Inzeria, They are differen- tiated from all other Australian forms of fazerla and from /. rocrogulii Krylov and & djejimi Raaben by their very infrequent branching, consistently gently convex laminae (grading to low-conical rather than reclangu- far}, and their short Jength of columns. In hav- ing subeylinerical, erect, mbhed columns with nunverous niche-projections, they closely te- semble Russian specimens of /, tjorud Krvlov, hut differ in the thinness of the zone of columns; the dbsence of branching may simply be a consequence of the short length of columns, Unlike 7, tjeaiuest [rom the Southern Urals, steeply convex laminae arc absent. The microstructure with pinching and swelling or wrinkled dark laminae is similar, but the pro- minent concentrations of iron oxides along Fig, concordant solution surfaces are ahsent. Until bicherms are found in which the columns had the opportunity to grow to 4 greater height, so that the mode and frequency of branching can be determined, and which are less recrys- tallized. so as to preserve the margin structure. no reliable identification ts possible, Distribution: Middle limestone band of the Wundowie Limestone Member, Umberatuna Group: Burr Well, northern Flinders Ranges, 8. Aust. Age: Late Adelaidean, correlated with the Late Riphean or Wendian of the USSR, fnzeria conjuncta £. nov. FIGS. 4h-m, 9d, 10d. 144, b Muterial: Three specimens from near Depot Creek. Holotype: S402 (Figs. 4a, b, tj, 14a), from the Brighton Limestone equivalent, 3 km north of Depot Flat H.S., southern Flinders Ranges, 8, Aust, Neme: Latin cenjurea, meaning joined, refers to the frequent coalescing and bridg- ing of columns, Diagnosis: Inzeria with broad, unwalled, rarely branching, frequently bridged und coalescing basal columns, which divide by «-parallel branching into narrower, unwalled upper columns with occasional e- and -parallel brinches, Niche-projections moderutely fre- quent, Laminae nearly flat to rectangular or gently convex, wavy or wrinkled, with a dis- tinct streaky microstructure. Deseriplion Made of Oeveurrence: Fiekd examination of bioherms is hampered by the very extensive lichen cover on rock, faces and by the discon- tinuous outcrop. Three domed bioherms, up to 50 m long, 3 m thick, occur interbedded in massive oohtic and intraclastic limestone, and cannot readily be differentiated from Acaciella augusta in the field, The basal, central portion of bioherms consists of flat-laminated stroma- tolitic limestone, passing up gradationally into bread columns, 5-20 em wide with frequent coulescing und massive bridges. Flat-laminated intervals may. intervene, At slightly different levels, the broad columns divide by a-parallel branching into 1-5 em wide columns. 3. (a) to fe)--—Gymiasolen cf. ramyay: from near Wilson, (&#)—S388, vertical columns pro- bably fron: a bidherm centre; (b) and (d)—S387, inclined columns interpreted to be derived from iw bioherm margin; (¢)—S389; (¢)—S390, irregular and frequently coalescing columns, Traced from slabs; (f} and (g)—Jnereria ef. tienes’. Wundowie Limestone Member, Burr Well, northern Flinders Ranges. $479. 102 W. ¥. PREISS S.A, Department pf Miaies Fig. 4. (a) ta (g)—lnzeria cf. umuasi, Wundowie Limestone Member, Burr Well, Northern Flinders Ranges. (a). (b) and (cy, $5942; (d). (f£), and (2)—S480: (c)—S479: (fh) to Gin)—lazeria conjuncte, Brighton Limestone equivalent, Depot Creek; (h), (i), and (j)—Holotype $402, broad basal columns branching into narrow colunms; (k)—S403; elangate columns from a bioherm margin; (1) and (m)—S398; narrow upper columns. SOUTH AUSTRALIAN STROMATOLITES I Caluma Shape und Arraigeneiu: Broad columns in lower part of biuherms subeytin= drical, up to 30 em high In their discrete por- lions, comMronly with rounded polygunal trans- verse sections, Where adjacent columns coulesce, or a wider columm branches, transvetse sections may be complesly lobate. Gverlying narrow columns slightly clongated, from 1 x 2 cm ty 3 x 5 cm in transverse section, up to 15 cm long between branches. Columns within central part of bioherm straight. erect (Fig. 4h, i,j) while at margins, they become inclined at 45°. slightly curved and strongly elongated (Figs. 4k, 14b), with swellings and constrice \ions franchiitg: Niche-projections are formed by unequal, o-parallel branching, or, less com- monly, divergent branching; the narrower column is set into the niche in the main wide column, Which generally resumes its former diumetec after the termination of the projec- lion, Where projections branch divergently, they protrude beyond the margin of the main column. Projections U.5=4 em tong. Within hroad column level, branching (other than by niche-projections) tare, Broad columns then divide by a-parallel, rarely §-parallel branch- ing, into narrower 1-5 cm wide columns, which hranch again, less frequently, by o- or #-parallel branching, In marginal zone of hio- herm, branching #- to +-pafallel, often with constriction at branching; niches stil] common, but clongated parallel to the long axes of platy colimns (Fig. 4k), Margin Structure: Lateral surface uneven, with very frequent. transverse ribs. same small pro- jection’, bumps, bridges, und accasional small peaks, Ribs, 0,5-1 cm wide. may be followed around the column periphery for a few cenu- metres. Both massive and delicate bridges accur between adjacent colunins, and, sametimes, between columns and projections, Niches in the column margins 4 to several centinrebres deep: some niches partly cloyed at one end (Fig. 4h). Occasional niches clongated trans- versely, grading into prominent ribs (Fig. 4h, ji. There is no wall; at the column murgins, laminae thin oanty slightly, and either end abruptly or turn down and wedge out; they do not envelop the lateral surface of the column f{Fig. t4a). Lamina sfape varices greatly from broad columns to upper narrow columns. In broad columns most laminae flat, geally convex, or reclangular (Fig. 9d). In plices laminae deve- lop to of more ¢rests, then either the column 103 branches (if near the branching level) or the Interspuce is bridged over. and the column re- sumes its normal growth (Fig. 14a}. In broad columns, measured values of h/d ore below O25. In the nyrrow, upper columns, laminae ure Consistently more steeply convex. OF those measured, 81% lic between 0,3 and 0.4, Col- umns in the marginal zone of hioherms have laminae strongly asymmetrical towards the ex- terior of the bioherms, commonly as steeply convex as in the upper narrow colamns ( 60%, of h/d between 0.3 wml 0.4). Fig. Md illues- trates the distribution of lamina convexites. All laminac wavy, with wavelength 2—+ mm, and locally wrinkled. Microstructure distinctly streaky with butt lenticular and continuous, wavy, swelling and constricting laminae, Dark laminee O,05-0,3 mm thick, wrinkled and wavy, with non-paral- lel upper and lower boundanes, sometimes atading into aligned clots and lenses, They consist of equigranular hypidielopie 10 idio- topic dolomite, grain size 6.005-0.0L mm. Crystals equidimensional and stained a pale green lint, responsible for thé green colour of the luminue. No individual grains of pigment could be resolved even at 1200 x magnifica- tion. Amplitude of waves and wrinkles 0.2-0.5 rom, wnd thickness of Iaminae changes rapidly within a few millimetres. Ligh leniinae consist of white to pale grey parily dolomitized sparry calcite of axenotopic to hypidiotopic texture, grain size 0.005—0,035 mm, tending to lens out near column murging where adjacent dark laminae merge. They also contain some coarser detritus, including fing sund-sized, well rounded quartz and feldspar, and small dolomite thombs similar to those of the durk Jaminac but less pigmented. Over most of the area of thin sections, dark laminae tend to be grouped into: macrolaminae 1-5 mm thick, which, like individual laminae, pinch and swell murkedty- There is evidence of minor contemporaneous erosion of thickenings and waye-crests of macrolaminze. Interspaces; Both lower broad and upper uar- row columns are separated by narrow inter- spaces, 1-20 mm wide, but columns from bio- herm mur'gins are almost in contact. The infill- ing sediment ts layered, either by sandy lu- Minac, or by single stromatolitic laminae bridging between columns, Interspace laminae ate depressed, concave upwards (Fig. 14n?. ‘The carbonate of interspsces is a dolemitized limestone: slightly inequigranular hypidiotopic calcite (partly recrystallized lime mud), grain PREISS WwW. Y. 104 wy SA, Depareoyern at tu FIG. 5 SOUTH AUSTRALIAN STROMATOLITFS I size 0.005-0.02 mm, contains subhedrul rhombs of dolamite, 0.005-0.05 mm diam, In places, quartz sand laminoe up to a few mil- limetres Thick abut against the column margins, suggesting that they postdate the growth of that portion of the adjacent column. No cur- bonale allochems were observed Av times of bridging, the structures had a relief of less than une centimetre, und bridging laminae may be only one or two centimetres apart. Secondary Alterqrion: Quartz and feldspar erains, oth in columns and interspace sedi- ment, have corroded bounduries; in pluces their margins ate completely replaced by carban- ate. While the dark laminae ure almost coms pletely dolomitized, the lime mud comprising the light laminae and the interspace filling is only patchily dolomitized and also contains hypidiotopic, coarser culcite due 1 partial re- crystallization. The dolomitization is probably secondary. Stylolites rare cacept in the bioherm margins, where they separate contiguous columns, Smull vughs. up to 3 mm diam, filled with course, twinned sparry calcite occasiooully cut across the lamination. The origin of the green coloration of dark Jaminae is not clear, since no particles of pigment could be resolved: the dolomite crystals themselves are tinted. Sunuce oxidation during weathering cither partly removes the colour, or depasils yellow- brown. limanite in interspaces or along style- lites. Comparisons The stvomatolites are difficult to distinguish in the field tram Acuciella cuynsta Preiss, but ure assigned le Jazeria on the following charac- ters! ribbed lateral surface, absence of wall, dominance of purallel branching, and niche- projections, The upper narrow columns also resemble Ketaviie and Kulparie but are dis- tinguished by the presence of long transverse ribs, the absence of a wall. and by microstruc- ture; unlike Katavia and Kulparia, their pro- jeettons are usually rounded, und set in niches. 7. conjuncta differs fram 7, tlamusi Krylov and /. mie Walter in having frequently coalescing columns, and consistently genily conver, wavy and wrinkled laminue; it lacks the consistently elongated niche-projections and the complex bioherms of /. intia. Unlike I. djejiri Raaben, its columins are straight, with frequent niche- Ins projections, and rarer branching. J. conjuttcte is distinguished from /. toctogulii Krylov by ily less frequent, dominantly o-parallet branch, ing, and by its coalescing and bridging, J. con- juncta is especially similar to Aldania sibirica in margin structure and mictustructure, but has more irregular and coalescing columbss. As pointed out above, A/dania night he hetter included in Jazeria. Distribution: Brighton Limestone equivalent, 3 km north of Depot Flat H.S.. southern Flinders Ranges, S. Aust Age: Late Adelaidean, correlfted with the Yate Riphean of the USSR. Inzeria multiplex f. nov, FIGS. 5, Ge, 1Ne, 14c, d, Sy Material: Six specimens froai figal Melrose and Yednulue. Holotype; S385, from the Brighton Lime- stone equivalent, 8 km NW of Mt, Remark- able, near Melrose, S, Aust. (Figs, Sa-i, 14, d). Name; Latin rudtiplex, meoning complex, manifold or with many parts, Diagnosly: Inzgeria with Trequent, dichotomous to multiple, a- and A-parallel to slightly diver- gent branching, and rarer branches arising from niches, Columns have irregular transverse sections. Margin bears ribs. bumps und shor projections. Laminae gently convex, smanth to wrinkled, with regularly streaky microstvuc- ture. Deseriprion Made of Occurrence: Due to poor outcrop, the exact mode of occurrence at Mt. Remark- able is not known; a kirge bioherm is inferred, since, when followed along strike, the stroma- tolitic bed passes into massive intraclastic limestone, but the contact is not exposed, Al Yednalue, the stromatolites form a very thick bed, which has not been waced Juterally. In outcrop, the stromatolites at Mt, Remarkable resemble literally linked forms, and columns becoine discernible only when the rock surface 1s Cut. Column Shape and Arrangement, Colunnis tuberous to subeylindrical, erect to inclined (Figs. 5; 14c, d), with steaight or gently curved axes: Occasional columns sharply bent, espec- tally when ussoci:ted with coalescing, Height Fig, *, (a) to ())—fazeria multiple, Brighton Limestone equivalent, southern Minders Ranges: (a-i)—Holotype $385, west of Mount Remarkable: ¢j, k}—S499. Flogt specimen, east of Yednalue, (1, m)—S498_ Outcrop specimens, cast of Yednalue. hits Ww. of columns between branching 4-21) emt, Trans- verse sections of columns round or rounded polygonal to irregular and lobate at points of branehing or coulescing. Columns which may be variously clongated, vary From 1 lo 5 em in diam. AL top of bed, columns frequently bridged by continuous, laterally linked layers. Branching very frequent and complex, either arising (fom niches in the parent column {Fig. Si). or, most commonly, by equal divi- sion (Mig. 5a, b, ¢), usually 2-parallel. rarely u- OF y-parallel, or slightly divergent (Figs. 14c, H5a). Adjacent columns frequently coalesce, especially in the upper part of bed, Marein Srructare; Column margin’ irregular, with numerous, short transverse ribs, low bumps and some Slizhily overhanging laminac. Bumps and ribs tocally grade into yery short, outgrowing projections, less than 1 cm long, which are more common than projections set. in niches, especially in the Mt. Remarkable specimens (Pig, 14d). There is no wall; com- monly gently convex laminae terminate at the column margin, without bending over, some- times overhanging to form sniall peaks and cornices. Small pertions of column margins relatively smooth. Bridges involving any num- ber of laminae are common, especiully near top of bec. Lanning Shape: Almost ulways gently convex (Fig, 9e}) even in the narrowest columns h/d docs nut exeeed 0,5, Ol laminae measured, 93% have h/d between 0.1 and 0.4, the made (40%) being in the range between U2 and 0.4 (Rig. Tey. Larminac may be dayhbly- crested, prior to branching, On a small-scale, laminag brondly wavy, and in places slightly wrinkled, Microsiructure: Alternalion of light, sparry laminae and dark, iron-stained laminae, with indistinct boundaries and varying continuity. In places, laminae grouped into macrolaminae 1 or 2mm thick. Boundaries between laminac frequently wrinkled. Light laminae (0.1-1.5 mm thick, usuilly constant weross the column width, smooth, wrinkled or wavy (Fig, 14c), with parallel wpper ynd lower boundaries. Varying abundances of fine: quartz sand and silt are incorporated in the light laminae, which consist of hypidiotopic to idiotopic carbonale. erain size 0.01-0,03 mm. Grains equidimen- sional, sometimes cuhedral. Dark laminae thinner, generally 0,1-0.5 mm, but pinch and swell geross the column width; crests wl laminae commonly thickesi Dark taminac V. PREISS erade [ron smooth fo wrinkled, and frequently become discontinuous, forming chains of clote and lenses up to 1 mm long, separated hy sparry carbonate (Fig. I4c), Dark laminac., clots and Jensex composed of reddish-brown iron-stained, xXenotopic carbonate, grain size 0.003--1.01 am, liiterspaces: Columns gencrally closely spaced, interspace width 1 mm-—* cm, The sediment es different in the two areas of occurrence. t1)At Mt. Remarkable, if is broadly lamnu- leU redilish dolomicrile; laminuc 1— mm thick. generally fist or slightly concave upwards Darker laminae generally thinner (up te | mm), of xenotepic dolontite of yrain size O.N03-—0,005 mm, alternating with thicker, paler, laminue, up to 4 mm thick, of xenotepic dolomile, 0,005-0.015 mm grain size, with a high pereentuge of terrigenous detritus. [angu- lar ynartz silt of grain size 0,02-0.05 mot, und occusionu) micu flakes). Intraclasls up to T cm Jong, 2 mm thick, locally present in interspace. generally siunding vertically or in- clined (Figs. l4e, d). (2) At Yednalue, the interspaces are filled with unlaminated sandy limestone, with quarts snd feldspar grains, 0.1-1.0 mm grain size, sub- rounded to well rounded, all embayed hv hypidiotopic to idiotopic calcite cement of grain size up to 0.6 mm, Sand grains mostly tightly packed, in places separated by a green- ish argillaceous matrix (Big. 15a). Secondary Alteration, Specimens from Mt. Remarkable consist entirely of dolomite, while those from Yednalue are calcite. Mt. Remark- able specimens are, however, better preserved: the idiotopic and hypidiotopic dolomite pro- bably formed during early diagencsis, but did not destroy the fine structure of the stroma- lolites. The dolomitic rock may have proved Mare resistant to later recrystallizalion, which has in both areas disrupted the fine damination to a greater or lesser extent, In adthtion, cleavage is well developed at Yednalue, and the columns are slightly deformed, sa thit metamorphism may partly account for the greater reerystallization here, Occasianal con- cordant slightly sutured stylolites follow the lamination, sometimes affecting xeveral adja- cent colunins, but all are cross-cutting ono fine scale. Greenish orgillaceous matenal is con- centrated in the stylolites. Some stylolites fol- low column margins and thus remove the Minor surface features of columns (Fig. 15a). Tectonic veins are filled with quartz or calcite. SOUTH AUSTRALIAN Compur/sans The stfomatelites arc assigned to Ingerta because of their ribbed columns with projes- lions, but they frequently resemble Baicalia in their tuberous shape; Baicd/ia, however. much more ollen hus divergent branching, more over- hanging lominae, and a distinctly banded microstructure. In having some a-parallel branching,, they resemble Kassiella Krylov and Acacielle Walter, but are distinguished by their Frequent f@-parullel branching and branching from niches, Inzeria sueltiplex 1s distinguished from f. rjomusi Krylov, 1 inva Waller, and /. confined Preiss by its very fre- quent branching. and rare projections set in niches. In these features it resembles J, focfe- eulti Krylov and J. djejind Raaben, but /. rocte- euiit has more regular, cylindrical colunins, while F. djenimi has steeply convex laminae. Distribution: Brighton Limestane equivalent; 8 km NW of Mt. Remarkable and 12 km E of Yednaluc, southern Flinders Ranges, S, Aust. Age; Late Adelaidean, corretited with the Late Riphean of the USSR. Group JLUIRUSANTA. Krylov Jiirusenia Kervlev 1963; S81. Raaben L964; 93, Krylov ir Rozanoy er af, 1969: 195. Cloud & Semikhatoy 1969: 1045- Semikhatoy, Komar & Setebryakov 1970; 166. Bertrand-Sarfati 1972: 52. Type Form: Jurisania cylindrica Krylov, from the Katay Suite of the Southern Urals. Digenoasis; Even, — parallel, — subeylindrical columns with round ot oval transverse sections and tare, dichotumuus g-parallel branching. Columns partly walled, partly bear downward directed peaks and overhanging laminac, fre- quently covered with an unlaminated selvige, Conen Jurusania cylindrica Krylov, J, tumuldurice Krylov, J. nisvensis Raaben and J, judemicn Komar & Semikhatov. J, shirica Jakoviey has been transferred by Krylov (1969) to a new group, Aldana, but Semikhatov, Komar & Serebryukov (1970) retain ils assignment to Junesanni, Bertrand-Sarfati (1972) has erceted new forms J. derbalensis, J, lisse, J. alte, Age: Late Riphean to Vendian, Jurusania burrensis f. nov, FIGS. Ga-l, YF 10f, 15b-, 16a Miulertalt Four specimens trom Burr Well. Hoefotype; S543 trom the upper limestone SUROMATOLITES 1 17 band of the Wundowte Limestone Menrber. Wirr Well, northern Flinders Ranges, 8. Aust. (Figs. bd. ¢, f, 15e). Name: After the Burr River, on the bank of which the stromatolites occur. Diagnosis; Jurusania with smooth to gently bumpy, partly walled columns and local, short peaks and overhanging laminae. Lamina shape gently convex to subconical, laminae lenticular with diffuse, streaky microstructure. Columns puttly covered by an unlaminuted selvage. Descripion Mode of Oecurrence; The stromatolites occur in lenticular beds af contiguous spherical and subspherical bioherms up to 2 m diam. (Fig. L5¢c). The bioherms consist of 3 concentrically arranged zones. capped hy an undulating columnar zone. Bioherm cores up to 50 cm thick consist of irregularly pseudocolumoaur and columnar-layered stromatolites of dark grey limestone, overlying sandy limestone with large, reworked intriclasts. Cores surrounded by concentrically laminated zone, from whith long straight, parallel columns arise. At bio- herm margins, columns slightly inclined, rarely subhorizontal: generally columns remain sub- parallel throughout the bioherm, but show more bridging and coalescing al. margins, Spherical bicherms, mutually in contact. over- lain by Mat or broadly undulating 1 m thick beds of columns with numerous bridges and pseudocolumns. Column Shape and Arrangement. Coluinns long. straight, purallel or radially arranged, cylindrical or subeylindrical. In one specimen from near the base of a bioherm, columns somewhat inclined. irregular, tuberous, und of strongly eblipuieul op Jobate transverse section (Fig. Gb, c); otherwise transverse sections round or slightly ellipticul. Columns mainly smooth, with only occasional low, hroud bumps (Figs. Ga-d, 15h, d, e); single columns gene- rally have constant diameter, 5-10 em for basal columns (Fig, 6h) und 2 em for upper, nar- row columos (Fig. 6d, ¢, £), Length of columns between branches nwy exceed 30 em; the whole columnar zone of bioherms is up ta 1 mi thick, Columns in the overlying undulating: bed rather short, and {frequently bridged, ap- parently arising trom basal, flat-laminated siromalolites (Figs. 6a, 6a, specimen S48. but the exact location of this specimen in the hioherin is not certain). Branching cather infrequent especially in nar- Tow, Upperthost columns, which may be up lo 108 W. V. PREISS SA. Department st Mines FIG. 6 SOUVH AUSTRALIAN STROMATOLILES 11 30 cm long between branches, but more often terminate their growth befere branching, Branching wlways dichotomous, either q-. or slightly B-parallel (Figs. 6g, b), Occasionully two neighbouring colunms miy cualesce, espe- cially in upper parts of bioherms. Margin Sirucinre geverally smooth, walled or unwalled, bearing only hroad Jow bumps several cm wide and of telicl up to 5 mm (Figs. 6a-h), Lamjnic generally approach the margin ul an acule aligle, but the actual margin is Lrequently removed by stylolites. In areas not aftecuod by stylolites. laminae either terminate at mareii, or extend down for u distance of up to |ocm to form a patchy wall (Fig. 15d, e). {ns a few places, laminae overhang slightly to form) small peaks, a lew mn long (Pig. Ge, f, 2), Larye overhanging peaks developed only an the irregular columns (rig. Ob). from the lower parts of bioherms. Considerable areas ul smooth columns coated with a xclyage, 0.2- 1.0 mm thick. of unlaminuted very fine grated culeite 1 Fig. 15d). Lamina Shape varies to some catent with column width, but most laminae gently convex with relief about | cm (85% have h/d between .2 and 0.5, Big, LOf): # Few narrow columns haye Lothian 76, Standley Chasm, Juty-Aug. 1954 (AD); Macorechie 443, Ser pentire Gorge, 19.vil, 1967 (NT), Makew minyma Macoiiochic, sp, nov, Feutex L-2 m altus, caulibus mojoribos nonnullis Peaeditus. Folia erecta, linearia, elongata, plana, fuevia, glabra, rigide corincea, 8-15 em longa, 5-8 mm tata, o [4-17 nervis. (usitale 15) lineata, si- floreseentia racemosu multiflora, thuchide glabra, 4-5 om fonga. Flores. maturi et expansi 8-9 mm Jong. Perianthinm gilvam, glabrum: torus circa | mm langim, OS ma tatum, horizontatls vel aliquantum obliquus, Ovarium pane sessile, gluh- ram, 1-15 nim longum; stylus glaber, filiformus, 3-6 mm longus; stigma labrum, ercetum, coni- cum, 1 mo longum, Glans ovoidee—globosa, ad basin avarii sita, Frets ovoideo—globusus, 2— 25 eny Jongus, 1-1.5 cm Jatuy: pedicellus 1-3 mm longus vel minusculus; rostrum perconspicuum, saepe curvatuin, Pericarpus laevis nisi pustilac Parvae, plus minus straminicolor. Semiuls serpus 8 mm longum; ala 1.? em Jonga, nigra. rhombi- formis vel angilato-ovata, secus corpus imilatera- liter, decurrens- Holotvpus: Macanochie 846, about 84 km W of Musgrave Park Station, S. Aust. (26° 20'S; 130°30’B), 30.ix. 1969 (NT). Speci- men with flowers, fruits and photograph. iwaiypie AD, BRI, CANB, K, MEL, NSW MERTH, ranges of J. R. MACONOCHIE. HM. microneura C. A. Gardner= nomen. inva- lidum in Fairall (1970), Strub (—2 im tall, with several main ytems- Leaves crect, flat, tinear, elongate, smooth, glabrous, rigidly coriaceous, 8-15 em long, 5-8 mm wide, with [4-17 nerves (mostly 15), Inflorescence a raceme with numerous flowers, rhachis glabroos 3.0-5.0 em long. Open mature flowers 8-9 mm long. Perianth creuamy-yellow, glabrous, torus about | mm long, 0.5 mm broad, horizontal ta slightly oblique. Ovary al- most sessile, glabrous, 1-1.5 mim long: style glabrous, filitorm, 5-6 mm long; stigma pliab- rous, erect, conical, | mm long. Gland ovoid- globular, at base of ovary. Fruit ovoid-globu- lar, 2-25 em long. 1-1.5 cm broad; pedicel [—3 mn or Jess; beak strongly developed, often curved, Wall smooth with small pustules, col- oured beige to light tan, the Iutler colour often more pronounced on beak. The beak is often lost From fruit older than twelve months and the wall becomes grey in colour, Fruit thea 1.9-2.0 em Jong and |.4-1.6 em brood. Seed bedy & mm long; wing 1,7 cm long. black, rhombic or angulato-ovate in shape, cecurrent along one side of the body. The specific epithet ts derived from the Pil- jantjatjara word minyma (woman). an allusion to the fruit's resemblance lo a woman’s breast. Aistribution; This species extends from. ihe Musgrave-Mann-Petermann Range complex of South Australia and the Northern Terri- tory down to the Tammin-Merredin urea in the south-west of Westeta Australia (Fig, 5). Seleered Specimens: ST. Duntop 2010, 48 km NE of Mt, Davics Camp, Mann Runge, 31x. 1970 (AD. CANB, NT); Larz 941, ca. 129 km NE of Mt. Davies Camp, edge of Pottoyi Hills, N.T_, 2,xi. 1970 (DNA, MEL, NT), S Aust, Eichler 17285, between Mi, Harriet and Musgrave Park Homestead. S.ix. 1963 (AID): Macererkie 846, ca, 84 kin W of Musgrave Park Station, 30,ix, 1969 (Type) «NTI, W. Aust. Gardner 839, Coolgardie, 4.x. 1920 (PERTH); George 2879. 35 km NE of Luver- ton. 23.viil, L961 (PERTH); Gearge 5639, 55 km SW of Wiluna, 29%.vii, 1963 (PERTH): Koch 975, Cowcowing, Sept 1904 (MBL, NSW, PERTH): Rovee 4461, Comet Yale, 23.ix. 1953 (PERTH). Makes francisiana F. Muell, 1858; 20, Type: G. Francis, near bay, Spencer's Gulf. Specimen probably lost (search made at AD, K, MEL). Nearype: RB. Copley 2345, Thirlga Station, Cluwler Ringes, S, Aust, |3.x, 1968 TAD), STUDIES ON SOME SPECIES OF HAKEA (PROTEACEAE) 131 i re ee as Shy emadeg- ABOLIMHSL NYIHIHON 40 Wh” fee cae, FeO WALOIOW O yn ivis Woeveeay Fig. 2 (above). Holotype sheet of Hakea minyma Maconochie. Fig. 3 (below). Holotype sheet of Hakea coriacea Maconochie. {72 ] tl. anultilinedta vir gramined lidum in Bairall (1970), Disiribution: Widely distributed theougl the southern arid areas of South and Western Ausa- tralia (Pig. 4), Selected Specimeny: S. Ausl Cornwall 56, ca. SS km SE of Kimba. ivi. 1968 (AD. NV): Rimyay $.n,. 113 km SSW of Camp 17. Elder nomen iWyVva- Expedition, July 1891 (AD, NSW): Wilyon (573, 40 kor NW of Ceduna. las. 1960 (AD). W. Aust) Gardner 6465, Bencubhin, T0.ix. 1942 (PERTH): Georve S646, 122 kin ™ of Sandstone, 29.vil, 1963 (NSW, PERTH): Hilyvan 31442 ca. 30 km SE of Londonderry. Idix. 1964 (AD, PERTH) & sa Distribution of A. fhuceutenta (m), H coriuced (&), and Jf: franeisinne (®), bin. 4. RSs hig 5.) Distribution of //. granunatophylla (®), Ho ominyma (@). He miutrilineata (a). From Kangaroo L, South Australia, there huve been two sterile collections made of a species close to /7. franeisiana, bur until better material is availuble, its status is obscure, Hakea coriacea Maconochie sp, nov. Frifex 3-4 1 altus, Folia linearia elongata, plana. eoriace’s intervenium pobescenti, 920 em Tonga. usitiite [4-17 em. 6-16 mm lata usitate 8-10 mm, » RK, MACONOUCHIE s—l4 hervis interns plerumque 9 vel LOL Lafleres- centia racemosa multiflora rose vel earneéa, cha. chide glibra, @=! 1 em longa. Ploy glaber 23-25 mim longus, pedicelluy 2-3) mm longus, perianthium 7-8 mm, stylus ghaber |9% 27 mm Jongus. stigma Wabraum. conicum 1.5 mm longum. Torys ali- qhanium cobliquus, ghins semi-annularis. Brae tea elabra vel pubertila, caduea, marine ciliata. Fractis ovoidea-globasus, circiler |& mnt jongus, 12 inm Jatus ef evassus, pericarpiis laevis nisi pus- lulne putteae purvae vel aliquando fissuris paucts. Affinis Haekede franeistinae Fo Muell sed differt numero majoro nervorum et foliibus latrioribus. Shrub to 3 to 4 m high. /eavey linear, Mat. coriaceous, with a fine pubescence on the inter- veinal area, 9-22 em long mostly 14-17 em. 6-16 mm wide. mostly 8-10 mm with S13 nerves. Inflorescence pink-red, rhachis glabrous 6-11 cm long, a raceme of many flowers. Flower glabrous 23-25 mm long, pedicel 2-3 mm long, perianth 7-8 mm, style ghibrous 19-21 nin, stigmatic cone 1.5 mm long Terns slighily oblique. ghind) semi-annular. Bracts glabrous or sometimes puberulous with ciliate margin, cuducous. Fruit woody. shortly pedun- culite (2-3 mm) about 1S mm tong, 12 mm wide and broad. wall smooth with w few small pustules or sometimes with small fissures. Closely related to AM. franciniane but differs in greater number of nerves and wider leaves. Holowpus: C. A. Gardier (2155, hetween Perenjori und Jibberding, W. Aust. Sept. 1953 (PERTH). Dis:ribmiien: Restricted to awn WSW of W. Aust. (Pin, 4)- Seleeied Speciinens: W. Aust. Aplin 1983. 3 kn EF of Tummin, 13.7%. 1962 (PERTH): Drupiniond (8. W. Aust. (MEL. NSW); Koch 1018. Coweowing, Sept, 1904 (AD, MEL, NSW); Melville 4265, U8 km W of Dalwaliina, 2l.vii 1953 (AD. BRI K. MEL. PERTH). ures in the Phylogeny and Evolution Tirese species form a natural group dillerine from the other members of Benthan’s Hekee scet. Conogvinoides ser. Longivivlee by the dis distinctly elongate raceme, 2-10 em Jong. ‘The other members of this series all have a more compact raceme, resulting in a more globular inflorescence. The phylogenctic relationships of this group are uneertain: (1) The inflorescence. leaf and fruit structure of HA. francisiena, HL. coriacea, MH. grammar. phyvlla and I. bucealenra indicate they pro- bubly have a common ancestor, and that J/ muiilineata and HH. tonvine may have evolved independently, STUDIES ON SOME SPECIES OF HAKEA (PROTEBACEAE) 133 (2) The similar distribution patterns of H. frencixiane and H. minyma suggest that these two. species may have had a common ancestor, and //, coriacea, H. grammatophylla, H. buc- culenta and possibly H. multilineata were all derived trom Al. francivsiana. The south-west province of Western Austra- lia appears to be the focus of origin of this group of species, as five of the six species occur there and the distribution tends to radiate from there into the more arid areas to the north and cast. The two records of Makeu ef. franecisiana for Kangaroo Island suggest thal, during an ¢arher geological period, Kangaroo Islund acted as a migration bridge between Eyre and Yorke Pen- insulas and Fleurieu Peninsula. Wood (1930) refers to this connection and rewards it as tecent in geological time. The implication of these observations is that either (1) this group of species may have evolyed, diversified and migrated during the period of a land connection between the Eyre and Fleurieu Peninsulas or, (2) this was a period of rapid spread of H. /ranersiana, The restricted distribution of H. gramsiio- phylla to the tanges of central Australia and the distributional pattern of A. francisiana would Indicate a north-eastern migration route from the south-west province of Western Aus- tralia, Subsequent periods of aridity would per- mit speciation to occur as there was a retreat to more favourable habitats. Acknowledgements The Directors and Curators of the follow- ing Australian Herbaria (AD, ADW, BRI. CANB, CBG, MEL, NSW, PERTH) are thanked for allowing examination of their col- lections and also Kew and the New York Bo- lanic Gardens. for making available Drum- mond’s type sheets, To Mr. J, H, Willis, | am indebted for two of the Latin deseriptions and to Dr. Hj, Eichler for his advice on nomenclatural problems and comments on the manuscript. References Benruam, G. (1870).—"Flora Australiensis™, Vel. §. (Reéve: London.) Brack, J, M. (1948).—Flora of South Australia’, Part Il, 2nd edn. (Govt. Printer: Adelaide.) CuHrpPpeNpALe, G. M. (1963).—The relic naire of some central Australian plants, Trai, R. Soe. 8. Asst. 86, 31-34. Eicutrr, Hj. (1965).—*Supplement to J. M. Black's Flora of South Australia”. (Govt. Printer: Adelaide.) Faimate, A. R. (1970).—“Western Australian Nutive Plants in Cultivation’. (Pergamon: Australia, ) Garpnern, C, A. (1936).—Contribuliones Florae Australise Occidentalis No. IX, J. R. Soc. W. Aust, 22, 123-128. Meisner, C, F, (1848).—Jn ©, Lehmann, “Plantae Preissianae” IJ, 260-262, (Hamburg.) MUELLER, F. (1858) —“Fragmenta phytozraphisde Australiae” Vol. LL (Govt. Printer: Mel+ bourne.) MUELLER, F. (1865).—"“Fragmenta phytographiac Australiae” Yol. Y. (Goyt, Printer: Mel- bourne.) MueELLeR, F, (1867)-—“Fragmenta phytographiae Australiae” Vol. Vi. (Govt. Printer: Mel- hourne.) Wire, C. T. (1944).—Contributions fo the Queenlsand Flora, No. 8. Proe. R, Soe. Qld §5 (5), 79-80. Woop, J. G. (1930),—An Analysis of the Vege- tation of Kangaroo Island and the adjacent Peninaulus. Trams. R. Soc. §. Aust, 54, 105- 139. PHOSPHORIAN LAVENDULAN FROM DOME ROCK MINE, SOUTH AUSTRALIA BY A. W. KLEEMAN* AND A. R. MILNEST Summary KLEEMAN, A. W., & MILNES, A. R. (1973).- Phosphorian lavendulan from Dome Rock Mine, South Australia. Trans. R. Soc. S. Aust. 97(2), 135-137, 31 May, 1973. A new variety of the rare mineral lavendulan (= freirinite) has been found in Precambrian rocks in South Australia. It is notable for containing a significant amount of phosphorous replacing arsenic. Its formula, based on microprobe analysis, is (Naj.o7Ca1.91Cu4.go) (AS3.16P.s4)O16Cli ss 4H20. Powder diffraction data are also recorded. PHOSPHORIAN LAVENDULAN FROM DOME ROCK MINF, SOUTH AUSTRALIA by A. W. Kieeman* and A. R. MILNES} Summary KreeMan, A. W., & Micyes, A. R. (1973),.—Phosphorian lavendulan fram Dome Rock Mine, South Australia. J'rans. KR. Soc, §. Ausf. 9742), 135-137, 31 May, 1973. A new variety of the rare mineral lavendulan (= freirinite) has been found in Precam- brian rocks in South Australia, It 1s notable for containing a significant amount of phos- phorous replacing arsenic. Its formula, based on microprobe analysis, is (Nay .o7Car.o1Cuy.so) CASy 43P.94)0i6Ch a5-4HeO. Powder diffraction data are also recorded, Tntroduction The Dome Rock mine is situated about 44 km ENE of Olary (148°27’R, 31°55/S). The detailed geology of the mine area is described by Dickinson (1942) and a brief description is given by Campana & King (1958). The country rocks are low grade metamorphics of the Willyama Complex: Dickinson considers the lodes ta be replacements of a fine grained sandstone. The primary ore is reported by Campana & King to be chalcopyrite and pyrite. Some cobalt is found in the sulphides and ery- thrite stuininys were reported by Mawson in an unpublished report to the Dome Rock Cop- per Mining Co, The fodes are oxidised to a depth of about 60 metres. The oxidised ore was inainly chalcocite, tenorite and cuprite, with olivenite and chrysocolla. Bayliss er al. (1966) examined specimens of oxidised ore from Dome Rock and reported several arsenic minerals occurring as “encrus- tations alony partings in siliceous ironstone”. They identified clinoclasite, Cu, AsO,(OH).. conichalcite, CaCu(AsO,)(QH), and a third mineral which they called chlorotile, Cuy (AsO,)4.6H.O with the comment that it also. =oresembled = mixite, Cu,,Bi(AsO,),; (OH),,, 6H:sO. However, chemical tests failed to reveul the presence of bismuth. They also record the identification of cornwallite. Cu, (AsO, ).(OH),.H,0 but do not quote the authority, Their own identifications were based on X-ray diffraction amplified by the chemical test on the “chlorotile”. Early in 1972, Mr, H_. Gallasch submitted a sample from the 120 ft. level of Dome Rock mine, containing a mineral which proved to be quite different from any reported by Bay- liss et al, The deseription of this mineral re- sembles that of clinoclasite given by Buyliss et al., but the powder patterns are dissimilar. Tt occurs as rosettes of ucicular blue crystals on u block of siliceous ironstone, The rosettes are about 2-4 mm in diameter and the individual crystallites are Jess than 0.02 mm_ across. Broadening of the lines in X-ray powder phato- graphs indicates that the mineral is in fact cx- tremely fine grained. The powder X-ray photo- graph suggested that it could be sampleite or lavendulan (Guillemin 1956). Accordingly it was decided to analyse it on the microprobe ta confirm its identity. Methods A polished thin section of some fragments af the mineral was examined in the C.S.1-R.0O. Division of Soils’ “Geoscan” (Cambridge In- struments) electron probe microanalyser, The elements As, Cu, Co, Ca, Cl, P. Mg and Na were detected during reconnaissance spectro- meter scans, Chemical homogeneity of the mineral fragments was checked by photo- graphing X-ray scanning images of the ele- ments of interest. Selected areas of the mineral * Department of Geology and Mineralogy. University of Adelaide. Adelaide, 5. Aust. S001. 7+C,S.1.8.0, Division of Soils, Glen Osmond, S, Aust. 5064, 130 fragments were then analysed quantitatively for these elements. Under normal conditions of analysis!, stg- nificant systematic drifts in count rate with time were observed for all elementy. This effect is possibly due to a combination of photo- chemical degradation (McConnell 1969) and thermal decomposition of the mineral under the influence of the electron beam in the eva- cuated specimen chamber (Sweatman & Long 1969). Loss of alkali elements from silicate minerals with time under the influence of elec- tron bombardment during microprobe analysis is a well known but not fully understood phenomenon (McConnell 1969; Siivola 1969), and can be minimised by reducing the beam current. In the present instance, however, the count rate drift was. minimised by expanding the electron bear so that it sampled a circular area 50 microns in diameter at the specimen TABLE i Micruprobe analysis 1 2 AssO;, 36.4 44,8 cud 38,2 36.3 CoO 0.03 nil CaQ 5.7 5.8 Cl 5.5 3,5 PO; 6.0 n.d, MezO 0.04 od. NasO 33 3.1 Total 95.2 O=Cl 1.2 Total 94.0 1. Lavendulan, Dome Rock Mine (analyst A. R. Milnes) 2. Lavendulan, San Juan, Chile (Guillemin 1956) TABLE 2 Stractural Formula Based an As-+ P—4 Na 1.070 Ca 1.014 Mg 0.010 Cu 4.800 Co 0.004 Total 6.898 AS 3.161 im 0.839 ‘otal 4.000 of 1.553 A. W. KLEEMAN and A, R. MILNES surface, and by driving the specimen beneath the beam at 30 microns per second during analysis, The accelerating voltage and beam current were maintained at 20KV and 50nA respectively. TABLE 3 Comparison of the X-ray diffraction pattern of the Dame Rock mineral with those of lavendulan and sampleite T.avendulan! Lavendulan? Dome Rock San Juan, Chile Sampleite2 dA I dA I dA I 9,20 vs 9.77 100 9.60 100 7.403 w 7.0) 40 6.85 70 6.76 Ww - 4.98 WwW 4.83 Ww 4.87 50 4.73 40 4.60 Ss 4.37 § 4.4) 40 4.30 80 4.17 s 3.89 70 3.50 vw 3.38 vvw 3.24 vvWw 3.23 50 3.18 vVw 3.12 8 3.11 70 3.04 100 3.06 Ww 2.98 vw 2.92 m 2.90 20 2.89 50 2.74 vw 2.76 20 2.80 50 7.69 m 2.69 50 2.61 m 2.47 m 2.48 20 2.50 50 2.40 Vw 2.34 vw 2.24 vvw 2.10 vw 2,02 vw 1.95 w 1.97 20 1.91 50 1,90 w 1.84 9 vyw 1.81 vw 1.83 20 1,79 710 1.75 m 1.76 20 1.72 vw 171 80) 1.69 yyw 1,66 vw 1,61 50) 1.50) yw 1.55 20 gar 70 140 w 1.47 20 1.44 1.42 20 1.37 70 1.21 20 1,21 50 1. Diffraction data measured by J. G. Pickering (C.$,1.R.0.) using a 19 cm camera and CoKa radiation. Diffraction data from A.S.1.M. cards Nos. 11-351 and 11-349, " 1 Normal conditions of electron probe microanalysis Accelerating valtage 20 kV Beam current S0nA Flow proportional counters Counting time: 10.seconds (line and one background position) Spectrometers: LiF crystal—CnKa, AsKs, CoKa, Caka Mica crystal—Naka, PKa, ClKe, MgkKa Beam fully focussed PHOSPHORIAN LAVENDULAN FROM DOME ROCK MINE 137 The raw output data from the electron probe were refined by the CDC 3200 computer program MICANCOR (written by H. Rosser of C.S.LR.O.), which incorporates the correc- tion program MKRPRB6 (Oertcl 1971). The mineral analysis reported in Table 1 is the average of analyses of eight selected arcas of the mineral fragments in the polished section, Results The X-ray diffraction pattern (Table 3) of the unknown mineral (measured by J, G. Pickering) is similar to the diffraction patterns of the isostructural minerals Javendulan Na(Cu,Ca) g({AsO,),;Cl4HsO and sampieite Na(Cu,Ca) ,(PO,),Cl4-5H.O. Therefore a structural formula was calculated on the basis of a total of 4(As+P) atoms (Table 2). The result given in Table 2 agrees quite closely with the data given by Guillemin (1956) except for the excess of Cl in our specimen. We have used the name lavendulan rather thun freirinite in accordance with the list. of New Mineral Names (Fleischer 1957). References Baviiss, P.. LawrRENCE, L. J., & Watson, N. (1966).—Rare Copper arsenates from Dome Rock, South Australia. Avst. J. Sci. 29(5), 145-146. Campana, B., & Kine, D. (1958).—Regional Geo- logy and Mineral Resources of the Olary Province. Bull. geol. Surv. S. Aust. 34. Dickinson. S. B, (1942).—The structural control of ore deposition in some South Australian Copper Fields, Bull. geol. Surv. S. Aust, 20. FLeiscHer, M. (1957),—New Mineral Names. Am. Miner. 42, 117-124. GuiLtemin, C. (1956)—Contribution a la miné- ralogie des arséniates, phosphates et vana- dates de cuivre. 1, arséniates du cuivre. Bull. Sac. franc. Minér. Crist. 79, 7-95. McConneie. J. D. C. (1969),—Photachemical degradation of a silicate in the beam of the electron microscope. Phil. Mag. 20 (8th ser.), 1195-1202. OsrTeL, A. C, (1971).—The calculation of re- sults in __electron-probe microanalysis. C.S.L.R.O, Division of Soils, Technical Paper No. 9. Strvota, J. (1969)—On the evaporation of some alkali metals during electron probe analysis. Bull. geal. Soc. Finland 41, 85-91, SWEATMAN, T. R., & Lone, J. V. P. (1969)— Quantitative electron probe microanalysis of rock forming minerals. J. Petrology 10, 332- 379, RHODACARIDAE (ACARI: MESOSTIGMATA) FROM NEAR ADELAIDE, AUSTRALIA. Hl. ECOLOGY BY D. C. LEE* Summary LEE, D. C. (1973).- Rhodacaridae (Acari: Mesostigmata) from near Adelaide, Australia. II. Ecology. Trans. R. Soc. S. Aust. 97(2), 139-152, 31 May, 1973. Serial collections of rhodacarid mites extracted by desiccating funnels from surface soil (greatest depth: 4 cm), moss and plant litter, at two sites on the western slopes of Mount Lofty, overlooking Adelaide, South Australia were studied, as were small collections of rhodacarids from two sites on the Adelaide Plain. The presence of two communities of hemiedaphic rhodacarid mites is demonstrated by differences in the characteristic species of two sites and a significant association into two groups of the species of one subfamily (Ologamasinae). Population density is higher in the wet, cool winter and where there is substantial, decomposing plant litter. Variations are demonstrated between some species in the number of generations per year, the time for occurrences of particular life-history stages and the sex ratio. It is suggested that species of Athiasella prefer higher nutrient loamy soils, while Gamasellus is almost confined to low nutrient, sandy soils. RHODACARIDAE (ACARI : MESOSTIGMATA) FROM NEAR ADELAIDE, AUSTRALIA. II, ECOLOGY by D, C. Ler* Summary buc, BD. C. (1973).—Rhodacaridae (Acari ; Mesostigmata) from near Adelaide, Australia. 1 Keology. Trans, R. Soe. 8. Aust. 97{2), 139-152, 31 May, 1973, Serial collections of thodacarid mites extracted by desiccating funnels from surface soil (greatest depth: 4 cm), moss and plant litter, at two sites on the western slopes of Mount Lofty, overlooking Adelaide, South Australia were studied, as were small collections of rhoda- catids from two sites on the Adelaide Plain. The presence of lwo communities of hemiedaphic rhodacarid mites is demonstrated by differences in (he characteristic specias of two sites and a significant association into two groups of the species of one subfamily (Ofogamasinae). Population density is higher in the wet, cool winter and where there {s substantial, decomposing plant Jitter. Varjalions are demonstrated between some species in the number of generations per year, the time for occurrences of particular life-history stages and the sex ratio, It is suggested that species of Athiavell: prefer higher nutrient loamy soils, while Gamascllus is almost confined to low nutrient, sandy soils, Introduction Rhodacarids are mainly predatory mites, and are most common and diverse in form in Southern Temperate regions. The present work formed part of a study on rhodacarids from the environs of Adelaide, South Australia (Lee 1970!), Part L dealt with systematics (Lee 1973) and should be referred to for the authority to names of rhadacarids collected. Part IIT, dealing with. behaviour, is to be pub- lished. Most rhodacarids are hemiedaphic, being free-living in surface soil, plant Jitter, or in moss or other plants with a similar growth form. Some taxa, however, are not hemie- daphic. Thus, Hydreagama@sus, Litogeamusns, Parasiliphis, Perisetus and Tangaroellus have only been found in or near the littoral zone, usually on rocky shares; Rhedacaropsis has anly been found in the littoral zone on sandy shores: Cyrtolaelaps or Eur)parasitus have generally been collected from bird or mammal nests or from but caves; Tangaroellus porosus Luxton has usually been found under the cara- paces of barnacles; and the two species of Laelapronyssus have been found closely associated with flies or termites. Ecological studies demonstrating more limited habitat preferences include only non-hemiedaphic thodacarid mites. Thus. Aydregamasus littor- dis (G. & R. Canestrini) mainly occurs in tock crevices in a limited part of the littoral zone(Glynne-Williams & Hobart 1952, Morton 1954). Rhodacarus and Rhedacarellus are commoner in the deeper soil layers (i.e. they are euiedaphic) and are limited to purts of sampled areas (Sheals 1957, Davis 1963, Wood 1967a, Emberson 19682), Cyrraluelaps and Euryparasitus are commoner in mammals’ nests that are on the ground and made of moss (Mrciak, Daniel & Rosicky 1966). There is a problem in defining precise habi- tats for ground inhabiting mites, because a species may occur in strictly limited habitats, * South Australian Museum, Adelaide. S. Aust. 5000. Yipr. D.C. (1970)—The taxonomy and general biology of the Rhodacaridac (Acari: Mesostig- muta). M.Sc. thesis, University of Adelaide, Australia (unpublished). “Emperson, R. M, (1968)— The Mesosiigmatu of certain coniferous forest soils in Western Quebec, with a preliminary account of North American Rhoducaridae (Acarina), Ph.D, thesis, McGill University. Montreal, Canada (unpublished). 144} Dp. Cc. hut nt Widely differing localities. For instance, it has heen shown in three different studies char Rhodacarus roxens Oudemans has a limited dis- tribution, It occurred only in a limited area jn minecul suil over iron-stone in grassland ( Davis 19631; in non-calcaveous drift around wu lime- stone Oulcrop in moorland (Wood 14¥67a}; and in allvial saltmarsh (Luxton 1967), This type of distribution for a number of species of mite led both Davis (1963) and Wood ({967b) to suxvest that many mite species consist of ecula- gical races with different demands upon the environment and therefore occurring in quite different habitats. The main aim of the present work was 16 demonstrate whether or not there ure any habi- (at preferences amongst hemieduphic thoda- carid mites. [nerdental information on seasonal fNuctuations. of populations and fifc-histories Was also sought, Th addition, becuuse species association was considered in relation to halvitat preferences, the correlation between taxunomic affinity and degree of co-existence is discussed. Four sites were initially sunpled befare two were selected for serial sampling. The results of the preliminary sampling from the two sites that were not sampled again are also given, be cause they suggest a possible correlution WelWeen certain genera and environmental factors. Methods Twe cxtraction methods were used: one for dealing with disturbed “bag” samples collected throughout a year and the other for undis- turbed “core samples collected in August. 1. Bag Sampling and Extraction Soil, down to a depth of approximately 4 cm, and the fitter or moss on it, was scouped inte a plastic bag with u trowel. The volume of a sample was about 1280 ml, and was taken From in area of approximately 250 cm, This sanple was poured intu an aluminium tube (14% 40 em) with a wire mesh bottom, which was placed on uy coarser wire mesh in 4 Cunnel (diameter of mouth—2?2 cm] leading down into a glass vial of 75% alcohol, The sumple was heated from above by a 40 walt electric light bulb for five days. Bay samples were collected once a fortnight for a year (24.1V.1968-23 iv.1969). On each occasion four samples were collected between IL am. and 4+ p.m. 2 From the Summit Site {Sel or S1), and 2 from the Foothills Site (Fel or Fl)—see appendix, One sumple of moss on soil and another of plant litter on soil were taken from each site. A totul of 108 samples weTe collected in the series, ibe 2 Care Sampling and Extraction Stee] core samples (5.15 em diameter x 4 cm uepth) were driven into soil covered hy moss or litter, dug out, and then sealed by a lid at each end. The volume of euch core was about 83 ml and from an area of approxi- mately 20 cm*. The steel cores, without lids, were inverted On wire mesh in multiple Tull- gfen funnels, so that the deepest part of the soil was uppermost, These funncly incorporated forced draught ventilation to prevent water condensation, The samples were heated from above by thermostatically controtled electric coils to 25° C for 2 days, tollowed by 30° C for 2 days. 35° C tur 2 days and finally 40° C for 1 day. Core samples were only collected on S.viii.1968 and J2,,ii1.1968, On cach occasion 16 cores were tiken from points evenly spaced throuvhout cach of 4 plots (S1, $2, FL snd F2}—see appendix to this paper. Samples from 2 plots (S82 tind F1) were covered hy « suh- stantial layer of fermenting plant litter, and the other 2 plots (S1 and F2) were covered by moss and 4 litle raw leaf litter. A total of 128 core samples were collected in the serus. Sites Four siles Werte sampled between the summit of Mr. Lofty and the coast-line of the Adelaide Plain, In the appendix, the Summit and Foot- hills Sites whieh were extensively sampled arc described in detail, while the Plains and Coastal Sites Fram which only small collections were made are given a briefer description, Two plots at each of the two former sites ure also des- cribed. Temperature and rainfall had linear gradients between the coast and Mt. Lofey: the former decreasing ond the lattes increasing with Neurness to the summit. On the other hana, the Sunimit and Coastal Sites were similar in hav- ing low nutrient, sandy soils, in contrast to the higher nutrient, loamy soils of the wo inter- venient sites. Three sites had a predominately Jiative Alora, while dhe Foothills Site had an alien flora, The sites that were extensively sampled (Summit and Foothills Sites) included areas which were elther almost entirety covered by plant litter or similarly covered by moss, Core samples were only collected from rectangular Plots in such Uniforny ures: one moss plot and one Jitter plot at each of the two sites, On the other hand bag samples were collected from larger areas including both plant Iter and moss patches. RHODACARIDS FROM NEAR ADELAIDE 14] RHODACARINAE ¢ : GAMASIPHINAE 143,136 /'60,119 ef Pa Fae yf \) e.- te ~ Ww el aS fh. eae ve ; aa i 3 Ly dk \ f ee ene i, Rhodacarus reseus * { \. f / oe \ i ate oad Fa Ne Eveplerius tilamentasus q i x ; . mn G alistralicus ott OF (12/00) fs - «i G 4 f 1 70,33 87,859 ; v S ¢ i a Gamasiphis K a ’ ' 1 : m ts wa ’ a a mm r o 6G fornicatus ¢ 324/ 20.8) oT “1 as ; ; G, Jenifornicatus ff 4 te: ¢0.0/5,23 é Antennolaelapns OGnchogamasus virguncula £0,0/ 7,0) A \ 7 ! SESSILUNCINAE Fig. 1. Species of Rhodacarinae, Gamasiphinae and Sessiluncinae collected during serial sampling, Dorsal views of adult females, Numbers given under names equal specimens (any stage) from the following environments: (Foothills Site moss, FS litter/Summit Site litter, SS moss). 142 bD. C. LEE Geogamasus howardi 0318, 643/41) OLOGAMASINI Athiasella relata 695)147/ 52,189 f Axiiassila Jettars “1, OLOGAMASINAE (503,102 /143,22) 503, 1102/1432 Hiniphis bipala co,o/s.0) GAMASELLINI Solugamasus mustela 634.7 / 0,0) Gumaselius cophinus ¢2,1/97, 9979 & Gamaselius tagardh| (5,0 /321,300) Ganiasellus concinnis (5,6 / 451,302) q i a \ bo . i Acugamasus puncranis i Ahodacareides minyaspis Agua BSUS PUNETATS VAcugamasus semIpunctatus’, (0,0/ 2,3) (0.0/9.0) se 29,0 / 1414) Fig. 2. Species of Ologamasinae collected during setial sampling, For further explanation sec Fig, [, RHODACARLDS FROM NHAR ADELAIDE Resalts |, Species und /orins represented Preliminary bag samples from Vhe Plains and Coustal Sttes in May and June, 1965, produced the following thodacarids (number of speci- mens in parenthesis): Plains Site—Rhedacaruy rosews (18), Gamasiphis australicuy (4), Athiasella dentata (29); Coastal Site—CGarmua- sellus grossi (13), Acugemasus elachyaspis (8)- lt would have been valuable to have pro- ceeded with scrial sampling at these two sites, bul becuse of a time limitation this was only done at the two other sites which supported more thodacarid species. Sizes and collection dates of preliminary samples from the Suramit and Foothills Sites were not comparable with thase of the other two siles and are theretore nor Jisted, Serjal samples from the Summit and Foothills Sites produced twenty-two species of rhodacarids (Figs. i, 2), A female Rhadaearetlus silestacas was listed (Lee 1973) from the Foothills Site, but this was taken while collecting miles alive for laboratory cultures. Such collections other- wise only included species taken in serial samples. Only a small proportion of immature chudi- carids were collected, The 3 species for which Tesulls are presented (Figs. 6, 7) produced it relatively high pruporlion of these stages, Further comments on immature siages are mide below under Section 5 (Seasonal Varia- tion), The sex ratio (male/female) of the 12 commonest rhodacarids From: serial samples is as Follows; Gamasiphis fornicatus, 0,26: Acu- gumiasiey . semipunciatux, 0.33, Geegamasus mininins, 0.344 Geogantasus howarel, 0.41; Gamasiphis saccus, 0,45; Gamasellus cephians, 0.56: Gamasellus concinius, 0.66; Antes nolaelaps celex, 0.67; Gamasellus tragardhl, 0.73: Athiasella dentata, 0.83. Euepicrius fila- meitosus, 0.845 Arhiasella relate, 1.23. 2. Differences between sites Numbers of specimens were as follows; Summit Site, 2784 (baz samples, 2)37: core samples, 647); Foothills Site, 3340 (hag sumples, 2707; core samples, 633}. Number ef species were as follows; Summit Site, 20; Foothills Site, 15. The majurity (13) of species were foun at both sites, but there was a considerable difference in the curmpusi- tion of the fauna. ‘Ihis difference is demon- straled by presenting the dominance anu fre- quency of the 12 commonest rhodacarids (Figs. 3, 41. Dominance is the percentage of the total 143 specimens that belong to a species, and is rep- resented by the size of a shaded urea in a collimn. Frequency is the percentage of samples in which a species was found, and is represen- led by the nuribers in the centre of a shaded area. Different species are characteristic (i.e. the most dominant and frequent) of different sites, 3. Differences between soil cover ef liter compared with moss Numbers of specimens were as. follows: litter, 3558 (bag samples, 2696; core samples, 862). moss, 2566 (bag sumples, 214%; core sainples, 418). A similar indication is given if the results from the core samples alone are expressed as rhudacarids/m? as follows; Sum- mit Moss Plot, 3450; Summit Litter Plot, AS60; Fuuthills Moss Plot, 3080; Poothills Litter Plot, 6310. Numbers of species from Summit and Foot- hills Sites were as follows: fitter, 21; moss, 19. The majority of species (18) were found in both litter und moss-covered soil. Comparing the dominance and frequency of individual species (Figs. 3, 4) it is evident that the species composition of a particular site is simiar whether it is cavered by litter or moss. ‘The preatest differences are shown by the core samples when the whole plot was mainly covered by cither litter or moss. Some species show distinct preferences: e.g. Athiasilla den- sate for litter; Gamasellus coptinus for moss. On the other hand. a preference at one site muy be apparently reversed at the other site, e.g. Geogamasuys minimis 4. Species Association (only Qlogamusinae) Exch site has dWferent characteristic species (see Section 2), mainly belonging to the Ologamasinae. To eslabhsh whether or not two communities ate present. the significance of associations in samples between species of Ologamasinae is examined. I have followed Dvebauche (1962) in usin o correlation co- eflicient based on 4 contingency chi squared test us a measure of degree of association or dissociation of species. The correlation coeflicients fron the results of bay samples (Table 1) produce the clearest pattern, Of the 28 terms, 18 ate significunt at the 1% level or Tess, ‘The species fall into two groups. One group (afhinselfa dentata and others) includes species characteristic of the Foothills Site. The other group (Geagiurasis tninimus and others) includes species charjc- teristic of the Summit Site. Since Adhiasella dentate and A. relata regularly occur al both ea) wl | U dD. 144 2) wi — Oo = < “ Oo < oO Footwits Summir Summit Foothills Species (Sci+51) CFci#Fy) Bhis Gamasi is} o 25959 Rs OG, rats it fi Phis Garnasi Hews s rts oe ky ser fctoeevi re [damentasus FuepiéHns =| a entat a. howard Athiaseua Geogamasus asus gam Geo! minimus Gomusellus sconcinAus Samasetlus ophinus D Gamaselius eee jamasus Acuy punctatus semi Olaelaps Antenn rhodacarids eclox Orher odacarids in bag samples — ¥ fs ge uo 2 as im = 9 2 on a w oo = Bu 25 =n] a eS we ar = Sa =m) =i) 5. 5S et Laney cal i) The dominance and frequency of the | (collected from 2 sites throughout th 145 RHODACARIDS FROM NEAR ADELAIDE CORE SAMPLES Summit ‘Summit Foothills Foothills Moss 5 rornicatu Gamasiphis seccus pPicrius Gus 7 >) G ° = el DQ filarm dentata Arhiaselia Athliasella pS eg Estes ar fe aS ce sierra oer STEEISET eoeeoenee_eetaes ee #ee s® ¢ e_e © 2 68 «Pe eee ee eee Oe Es Geogamasus Geagamasus minimus Gamasellys. SOnclany Gamasellus cophinuss: none 3 Gamesseltu Acugam. elaps Antennola chnodacsrids f thodacarids in core samples the dominance and frequency of the 12 commonest specics o Fig, 4. anation see text. (collected from 4 plots it early August). For further expl 146 D. C. LEE TABLE 1. Correlation of Ologamasinae species in 108 bag samples containing 4,844 specimens. Correlation indices (C X 104), +> (association) .— (dissociation), upper limit is 707. Species A.den. A.rel. Gow. G.min, G.cop,. G.con. Gira. Asem. Athiasella dentata +355 +448 —49 —142 —256 —197 —36 Athiasella relata (EY +307 iY) +57 —32 —4$ —t4 Geogamasus howardi Corey ES ee) —319 —495 —583 —S566 —299 Geogumasus minimus 0 0 (4/7) _ +517 +394 = |399 +58 Gamasellus cophinits 0 (///) Cet) +580 +598 +287 Gamasellus cancinnus (f//) 0 (f///) (PFti eer} +656 +396 Gamasellus tragardhi — 0 (//1) (FR) CeRRY (Fea) CR) Acugamasus semipunctatus ( 0 /f) 0 (ca a Gina +349 Significance of relations: None Positive Negative P> 0,1 0 P< 0:1 + = P< 0.01 (**) (//) P= 0.001 (ar G//) the Summit Site as well as the Foothills Site, (Arhiasella dentata—Garnasellus cophinus, there is, in the main, only a significant dissocia- tion between Geogamasus howardi und species al the Summit Site. The correlation coefficients from the results of care samples (Table 2) are similar to those of bag sumples but with 1 drop in significant associations. Of the 28 terms, 12 (6 associa- tions, 6 dissociutions) are significant at the 1% level or less. Although there are the same num- ber of significant dissociations, 3 are for dif- ferent pairs of species. The reduction in associations is only significant where a pair of species was either uncorrelated or significantly associated in bag samples while being signifi- cantly dissociated in core samples. This was true at the 1% level or less for three pairs Athiasella dentata—Guamasellus tragardhi, Acu- gamasus semipunctatus—Gamusellusy Concin- nus). Such a significant dissociation in core samples could have had a number of causes: smaller sample size isolating niches; sampling separate moss or plant litter covered plots (one at each site was outside the area used for bag sampling), thus isolating niches and possibly introducing new ones: fewer mites per sample; no seasonal effects such as the absence of any rhodacarids [rom mest summer samples. The conspicuous change in dominance between bag and core sampling of Acigamasus semipune- ratus In “Foothills moss” samples and Gama- selius trragardhi m “Summit litter” samples sug- gests that the significant dissociation in core TABLE 2. Correlation of Clogamasinue species in 128 core samples containing 1,280 specimens. Correlation indices (C X 108), + (association), — (dissociation), upper limit is 707. Species a.den, A.rel. G.how. G.min, G.cop. G.eon. G-tra. A.semi. Athiasella dentata +355 +369 —i06 —3&2 —24 —327 —205 Athiayella relata Soaiea | +10 +49 —85 +87 —156 —35 Geogamasus howardi (*#*) 0) =—344 —309 —418 —203 +30 Geogamasus minimus 6 0) (///) +213 +322 +161 —If6é Gamasellus cophinus (///) 0 f/f) = +264 4236 —102 Guamayellus corcinniy 0 0 (///) (+#*) (er) —20 —231 Gamasellis tragardhi (///) —_ _ + (F*) 0 4355 Acugamasus sermipunctatus _ 0 0 — 0) (//) (**) Significance of relations: None Positive Negative P> 0.1 0 P< 0.1 + — P< 0.0L (#* (fA < 0,001 (*??) (//1) RHODACARIDS FROM NEAR ADELAIDE samples of the above pairs including these species is due to the difference in arcas sampled. The same cause may apply for the dissociation between Athiasella dentata and Gamasellus caphinus. Seasonal Variations Seasonal fluctuation in total numbers of rhodaearids at each site based on bag sampling are summarised in Fig. 5. There was a con- spicuous fall in numbers of rhodacarids in samples collected during the summer (Decem- ber-February). This is associated with a drying out of the environment and rainfall figures for Stirling (5 km SSE of Summit Site) are given as a factor closely associated with this process. The low number of samples taken means that seasonal differences indicated for the two 5. 147 sites are tentative. The number of rhodacarids from the Summit Site was fairly constant throughout the wetter months (May—Novem- ber). At the Foothills Site the rhodacarid population apparently gradually increased in September and October to a peak, which was nearly twice the highest number at the Summit Sitc. If this change is true for the actual popu- lations it could be telated to the dominant genus at the Foothills Site, Arkiasella, being multivoltine, while abundant species at the Summit Site are univoltine (see below). Seasonal fluctuation in numbers of the dif- ferent developmental stages and sexes of Gamasellus concinnis, Gamasellus tragardhi and A thiasella dentata are represented by histo- grams (Figs. 6, 7). Not enough immature APR MAY JUN Jui AUG sep oct NOV DEC JAN FEB man APA T 1 | | ] ‘ftw TT T T T ts a RHODACAAIDS COLLECTED eee TOTAL pe M--aAT FOOTHILLS SIE —t3a0 |— @--ar SUMMUT SITE hae NUMBER L. a / ao an - . ™ 150 7 / OF . s a 5 |__ a7 fod ae \ / on e"-8 a a Ll s A fo N x bd s—a— By a a“ BMECIMENS L. e ‘~,—s 0 ‘\ / \ = \ } e PY 150 e ae \ to e—e-* s a \ va \ ran Jf ‘ ) ‘ a o. s— 6. at} — e Na \ 50 X s—e_ i o—*_, ~e fs RAINTALL AT STIRLING ¢ NEAR SUMMIT SITE) + #.—-AcTUAL FORTNIGHTLY fA. | | » oy. O---AVERAGE MONTHLY B Z me * "Y= |. y, ee 7, & [4 eo + |_ > a RAINFAL | 4 “sO “¢ ys, 2 ke af + \ ss IN - \ a , \o ’ 4 bares “ ls r he re im 9oNY -~ vo ot) o L_ + + + \ th ft, =I. | Le al | | TIME OF ‘YEAR Fig, 5. Scasonal fluctuation in numbers. of Rhodacaridae collected in bag samples at two sites during 1968 and 1969. Rainfall records are for nearby Stirling. 148 D.C, LEE stages of the other rhodacarid species were col- lected to warrant presentation here. In Canada, where the winter is extremely cold, Gameasellus vibrissatus (which is mor- phologically very similar to G. iragardhi) over- winters as adult females which give rise to a single generation in the following summer (Emberson—footnote 2). My results show that Gamasellus tragardhi (Fig. 6) bas a similar life history, except that it over-summers as adult females and males which give rise to a single generation in the following winter. Gamasellus concinnus (Fig. 6) is also univol- tine, but over-summers in the deutonymph Stage, the males emerging before the females at the onset of the wet season, Arhiasella dentata (Fig, 7) probably over-summers in the adult stage and it breeds for a longer period, prob- ubly being multivoltine. Results for some other species (Lee—footnote 1) are inadequate but suggest the kind of life-history that they have. Geogamasus towwardi, Athiaxella relata and Euepicrius filamentosus appear to have similar life-histories to Athiasella dentatu. Gamasiphis vaccus and Gamasellus cophinus may be uni- voltine and over-summer in the egg or early immature stages. It is noteworthy that the life-histories indi- cate that there are large numbers of rhoda- carids (e.g. deutonymphs of Gamasellus con- cinnus) in the soil during the summer that were not represented in the samples considered here, Possibly they moye down deeper than the surface 4 cm sampled. There is no clear indica- tion that rhedacarid species stagger their life- histories so as to avoid exploiting the environ- ment concurrently. Discussion The twelve commonest. species of rhoda- carids in serial samples were found at both Summit and Foothills Sites, but each site had ee a y GAMASELLUS CONCINNUS GAMASELLUS TRAGARDHI [ FEMALE i oo zie Fr = aa 4 a. a a MALE no of I 7. DEUTON.| is ss i ints ZF Ee ls ad atrnnd oma Ae tae dans PROTON. eo oh) 79 35 (Eom: oe =a = i fs ato eb APH IMAY! JUIN | JUL) ALS! SER Oct NOY! DEC! Jan] Pea) Man) APR SE POR VTE ! gba tbat a | APRIMAY | JUN [JUL | AUG) SEP OCT NOV |DEC. JAN LFEBIMAR APR/ Fig. 6. Seasonal fluctuation in numbers of individuals at different developmental stages of Gamasellus a concinnus and G, tragardhi collected in bag samples at two sites during 1968 and 1969. RHODACARIDS FROM NEAR ADELAIDE 149 = frmale oe Mate = = 2 a BEUTON, rm ‘aL, > = 3|. an PROION mom [tanya A On sO On APA MAY ALM dol pale SFP Oa|NoY, Jeo inn Poe lmAR Apr Fig. 7, Seasanal fluctiation in numbers of in- dividuals at diferent developmental stages of Athfasella dentate collected in bag sanupiss at two sifes duting 1968 and 1969. different characteristic species and amongst members of the Ologamasinae there was a highly significant association between species characteristic of a site, thus demonstrating the presence of two rhodacarid communities, Because serial samples were only taken from two sites (Summit and Foothills Sites). and environmental factors were not measured, it is impossible to confidently associate the rhoda- carid taxa with particular factors in the envir- onment. If, however, the few samples from the Plains and Coastal Sites are considered, there appears to be a similarity between the rhoda- carid faunas of the Foothills and Plains Sites, in that Arhiaselia had the biggest representa- tlon, and between the Summit and Coustal Sites in that Gamesellus had the biggest representa- tion. It appears, therefore, that the coastal sand dunes as well as the low nutrient, sandy soils near the summit of Mount Lofty are favour- able to Garnayellus while the higher nutricnt, loamy soils of the foothills and plain are not favourable. The converse appears to be true for Athiasella. Factors such us temperature and tainfall, which have a linear gradient between the coast and the summit of Mount Lofty, do not appear to be directly favourable or un- favourable to particular taxa. Tt is noteworthy that although the flora at the Foothills Site was introduced, mainly from outside Australia, the gamasine fauna was predominantly rhodacarid, with characteristic species that are probably all eidemic to South Australia and belong ta genera probably endemic to Australia, Although the composition of the rhoducatid fayma of a particular site was similar in soil samples covered by litter and those covered by moss. a few species showed a distinct prefer- ence for one or the other habitat, Other attributes revealed for certain taxa were the iendency for species in the same genus to have similar scx ratios and the specics of one genus, Gamasellus, to follow quite different life- histories. Species of some genera (Arhiasella and Gamasellus) were characteristic of one site, while for other genera (Geogarnasus) this was not true. Conflicting hypotheses on species association were resolved by Bagenal (1951). who stated that “related species are more likely to be found in similar, though not identical, habitats than are unrelated ones”. Hurlbut (1968), working on species belonging to families closely allied to the rbodacarids, reached a similar conchision expressed as “species which are very different anatomically or very similur anatomically coexist less often than species which are moderately similar to each other’. Certainly the three species of Gamaselluy associated at the Summit Site are as dissimilar (see Fig. 2) from each other as it is possible to select from known species of Gamasellus and would probably be considered by Hurlbutt (1968) as ‘moderately similar’. They must exploit different ecologtcul niches within the volume of the small cores in which they were cqilected. The same is likely. although not so clear-cut for the two species of Athiasella, 1 The very slight but easily discernable mor- phological difference between Gamuavellus tray- ardhi from the Summit Site and Garmasellus grossi from the Coastal Site (Lee 1973) sug gests that the level of taxonomic distinction is closely associated with ease of anatomical diap- nosis rather than genetic similarigy. The Rhodacarus specimen from the Summit Site is possibly equally dissimilar to the Rioducaruy specimens From the Plains Site (Lee 1973). both ef which I have refetred to R. rosens, 1 suspect that many mite species which show limited distnbution in widely differing geo- graphical locations (see Introduction) are also grouped in one species because of difficulties in diagnosis, D. C LEE Acknowledgements Tam indebted to Dr, K. E, Lee for the use o£ Tullgren funnels at the Soil Zoology Section of the C.S.LR.O. Soils Division, and for his comments on this manuscript, I also acknaw- ledge the helpful advice afd criticism received from Dr. D, A, Duckhouse, University of Ade~ laide, during the preparation of the M.Sc, thesis which formed the basis of this study, Lam most grateful to Mrs, Curol Aitken for Preparing some drawings (Figs. 5-7) and to Mrs: Brenda Head fer preparing the other drawings (Figs. 1-4) as well as to Mrs, Jo Bramley and Miss Debbie Rankin for carefully typing the manuscript. References RagewaL, T. Bo 19511—A note on the papers of Elton and Williams on the generic relu- lions OF species in smal! ecological com- munities, f, Anim, Ecol. 20, 242-245. Dayis, B. N. K. (1963).—A study of micro- anhrepod communities in mineral soils near Corby, Northants. J. Anim. Ecol. 32, 49-71, Denaucnr. Hy R. (1962).---The structural analysis of Animal Communities of the soil. Jy PW. Murphy (ed,}, “Progress in Soil Zuvlogy". pp, 16-25. (Butlerworth: London, } GLYNNE-WILLIAMS, J, & Hopart, J. (1952),— Sludievs on the crevice fauna of a selected shore in Anplesey. Prov. 200! See. Lond. L22, 797-824. Nurteure A.W. (1968), Coexistence and atia- tomical similarity In two genera of mites, Veigala and Asca. Syst, Zoal, 17, 261-27). | ke, BD, C. (1973)—Rhodacavidae (Acari: Mesas- tigmats) from near Adelaide, Ausiraliu, 1. Systematics, Ree. §. Aven Aldus. 16 114), I- af. liicHrienp, W, H. (1960).—Soitly on the western Slopes of the Mt. Lofty Runge near Adelaide and Elizabeth, South Australia. Divi Rep. Div. Swils CSIRO 8/59, 1-36, Luxvon, M, (1967)—The Zonution of Saltmarsh Acarina, Pedobiolagia 7, 53-6, Morton, J. E. (1954)—The crevice faunas of the Upper intertidal zane yt Wembury. J. mar, bivl, ayy, U.K. 33, (87-224, Meciak, M., DanteL, M. & Rosicky, B. (1966),— Parasites and nest inhabitants of small mam- mals in the western Carpathians, 1. Mites of the superfamily Gamasoidea (Purasitiformes), deta Fac, Rerum nat. Waive. eomen.. Brarist., Zook 13. 81-11. SHeaus, J. G. (1957)—The Collembola and Acaring of uncultivated soil, J. Anin. Eeol. 26, 125-134. Sencar, R.L.(1972).—"The vegetatinn of South Australia’. (Government Panter: Adelaide, ) Server, R. £,, & Perey, R, A, (1948).—The Plant ecology of part of the Mount Lofty Renaes (1). Troe. Ro Save. 8. Aust, 72, 91- 132. Woop. T, G. (1967a).—Acari and Collembola of moorland, soils from Yorkshire, England. |. Description of the sites and. their populations, Oikos 1B, 102-117. Woon, T. G. (1967b).—Acari and Collembola of moorland soils from Yorkshire, England. 1. The micro-arthropod communities. Oikey (8, 277-292. Appendix: Details of Sampling Sites and Plots Summit Site, Locations Mi. Lofty, near ta sum- mit, approx. 18 kin trom the sea, Australian Map Grid vo-grdinales: 290600 nv E/61272320 m N, map fo. 6628-48-j, Dept. of Lands, Adelaide. Height above sea level: 640-670m. Rainfall: mean annual vaintall approx. 120 cm; figures osed in graph (Fig, 5) are for Stirling (5 km SSE of site) with a man annual rainfall of 119.0 cm, and 4 total rainfall in 1968 of 161.6 cm; it should be noted thal “a large percentage of soinfall is lost to the soil by run-off an the Adelaide Hills” (Specht & Perry 1948). Temperature’ mean monthly min./max, temperatures for Stirling are January, 11.5°/24.5°C; July, 4,5°/10.5°C. “Ver- rdiny steep western slope of hill, near to summit, Soil: Black Hill Assoclation—“low nauicient re- server im most Soils in Which shallow depth is the chief limiting physical churacteristic’ (Litchtield 1960); shallow (10-35 em}, dark grey, loamy sand; an analysis of soil fram Mit, Lofty Summit showed 0.004469 PO; und 0.0405 Nitrogen (Specht & Perry 194%). Vegetation: open-forest of Stringy Burk—Ficwalypiws obliga LoHérit.—with a sclerophyllous understorey of small native heuth shrubs including Banksia ornatr FVM. ex Meisn., EZpucris dipressa Labill. and Leptosper- mum juniperinum Sam, Fifteen other species of native shrubs. herhs or grasses were collected from the site. Ceneral Snmmreit Plot (Sel). A sub-thombaid RHODACARIDS FROM NEAR ADELATDP 1S] area (approximaely 1% a 12 m) which ¢on- sliluled @ clearing ymanast charred trees with q draingge channel ronning through the centre A fire had passed through the plot three years before (February, 1966). The eastern half of the clearing had substantial vegetation, includ- ing abundant fireweed—Sacielia achilleoides R. Br. ex Ait. a sheart-lived, “high-fertilily-de- manding” species depending on the temporary rise in fertiliiy-level due to the ashes of the burnt vegetation (Specht (972). The western half of the clearing bad 9 sparse vegetation of heath shrub seedlings and extensive patches of moss. Plant Hitter was almost absent from the mossy half of the clearing, but had wecumu- lated as raw leaves and twigs around the bases of tree slumps. Fallen branches and smail shrubs in the other half, Bag samples were collected from this plot. Sammit Moss Plar (Si). A rectangulur area (2 x 10 mj lying approximately at the centre of the western half of plot Sel, Covered alniat entirely by on mat of moss. All core samples, and after August some of the bag samples. were collected fram this plot, Summit Liter Plot (S2), A rectaneular area [2 x 10 m) lying approximately 20 m casi of plat Scl. and separated from It by a bilamen toad, No fire had been through the plot for 25 years. Understorey Was thick with heath shrubs und decomposing plant litter (mainly 1.0 cm deop) covered most of the ground, Only care samptes were collected fram this plot, Foorhills Site, Location: Foothills of My. Lofty. approx, 16 km from the seu. Australian Map Grid co-ordinates: 288230 ot E/4127620 m h, map no, 628-49-e, Dept. of Lands, Adelaide, Hetght above seo level; 240-270 m. Ruinfall: mean annual rain- fall is appros, 94,0 cm. Temperature; mean monthly min,/max. temperatures for Glen Osmond (§ km W of site) ave January, 16°/28°C; July, 7° ¢1S°C, Terrain: hattom of steep northern slupe (south-Facing aspect of ridge] of Waterfall Gully, just west of First Waterfall, beside an artificial pond formed by dredging and damming First Creek, Soil; Osmond Association—“Nutrient te- Serves presumably intermediate hetween law levels ... and the moderate levels in the red brown carthy af the piedmont aprons” [Litchfield 1940): shallow ta deep (35-110 cm), allavial red- brown loan, artificially mieved to present position, possibly from creek hed. Vegetation: alien {is it mainly i& on bottom 15-20 m of slope downstream from this point. further up slope from site there are Manna Giums—Encalypris virinelis var, huheriana (Naudin) Burbridge-and Drooping Sheoaks—Caxaerina stricta = Ait}; Fan-leaved palms (i.fvistonia sp.), Olives (Olea europaea L.), Lilacs (Syringa wileari« L.) and Fitfesperim (tn fiefarien Vent, (native of eastern stutes); under- storce of brambles, bracken und live species of herhs and grasses; only native plant found was a small hetb—Gerunium pilosan| Forst, Gereral Foothills Plor (Fetj. A sub-rectanga- lar area (approx. 20 © 8 m) which constitited a patch of quile thick alien vegetalion on the north bank of the pond, Although the bunk was steep, the understorey held the plant toec in nest places. but where the hank was very sleep, or the ground stony, there was lillle or no litter and moss or liverworts grew. Bag samples were collected from this plat. Foothills Litter Plot (F1). A rectungular urea (2 © 10m) tying spprex, at the centre of plot Fel. Covered by plant litter (Olive leaves. pre- dominated, mainly 2.0 em deep) and some herbs and eruss tussocks. All core samples, and after August same of the bag samples, were collected from this plot. Foothills Moss Plot (P21, & rectangular qred (2 x 10 m) lying approx. 10 m west of plot Fel. und separste! from ic by si artificially channelled creek bed. Which was stecp and usually dry. Some soil bare but mostly covered by moss or liverworts. Under a row of snaall trees (Pitresporam endalitem) evenly planted along the west bank ot the creck. Only core sumples were gollected from this plot. Plainy Site, Location: Heywood Park, Unley. an the Adelaide Plain, approx. & km from the sea Australian Map Grid co-ordinates: 280810 m E 6128350 m N, map no 6628-50-e, Bem of Lands, Adelaide, Height above sea level: 30-A0 m- Rainfall: approx: 38 cm/yeat. Tensperature: January. [6.4°/29.8°C, July, GS /I45°C, Ter- rain; small, flat suburban park, wilh fall frees sur rounding clearing, Sojl; Edwardstoawn Association; red-brown loum. Vegetation: savannah woodland of River Red Gums—Encotyptus camatdulensis Dehnh—"is confined to grey-brown podsols on jhe slopes and ridges and alluvial soils in the valleys, both soils being rich in PaO; and nitrogen and having high water relations” (Specht & Percy 1948): understorey of grass amongst patches of Fuculyprix liter, Samples fram patches of litter under River Red Guo. Coastal Site Location: “Pinery”, Grange Golf Course, near cost of Adelaide Plain, approx, 1.3 km from the sea, Ausiralian Map Grid co-or- dimales; 271910 m E/6137D40 m W, map no, 6528-36-m, Dept. of Lands, Adelaide. Height above sea level: #30 m Rainfall; approx, 43 em/yearm “greens” artificially watered. Tempera- jure; January, 19°/28°C: July 6.5°/15°C Ter- rain! inland relicts of coastal dunes formed in Pleistovene Period, modified to .a golf course. Soil: Osborne Association; calcareous sand in which the soluble calcium bicarbonate has been leached to lower horizons. Vegetation; low woodland of Native Pines—Callitris preissti Mig.—-with under- storey of mioss and sparse grase, on dune ridges, amongst artificial grass wreens; “a “degraded” climax plunt community characteristic of infertile. fien-calcareous, sandy snifs” (Specht 1972), Sumples from mots mats under Native Fines, st ase 31 AUGUST, 1973 TRANSACTIONS OF THE INCORPORATED CONTENTS Watson, Jeanette E. Pearson Island Expedition 1969—9. Hydroids - el 5S Burn, Robert Pearson Island Expedition 1969—10. Opisthobranchs_ - - 201 Seed, W. F. Pearson Island Expedition 1969—11. Crustacea: Isopoda rey, Daily, B., & Milnes, A. R. Stratigraphy, Structure and Metamorphism of the Kanmantoo Group (Cambrian) in its YER Section East of Tunkalilla Beach, South Australia - - - 9G Pails} PUBLISHED AND SOLD AT THE SOCIETY’S ROOMS STATE LIBRARY BUILDING NORTH TERRACE, ADELAIDE, S.A. 5000 —— ee eee we Doe PEARSON ISLAND EXPEDITION 19697-9. HYDROIDS BY JEANETTE E.. WATSON* Summary WATSON, JEANETTE E. (1973) . -Pearson Island Expedition 1969.-9. Hydroids. Trams. R. Soc. §. Aust. 97(3), 153-200, 31 August 1973. Intensive collecting of the sublittoral hydroid fauna of Pearson Island in the Great Australian Bight, in January, 1969, yielded 81 species (with 3 varieties in one species), of which 13 species are newly described. There are 18 new records for South Australia and 1 new record for Australia. The collection permits a fuller description of seyeral hitherto poorly known southern Australian species. Collections were made using SCUBA at 3 localities representative of environmental extremes on the coastline-a rough-water site exposed to prevailing swell, a sheltered embayment, and a deep water situation in open ocean. The deeper water fauna contained species already known from deep dredgings in the Great Australian Bight, but differed markedly from the collection from shallower water, with only 1 species common to both. The Sertulariidae and Plumulariidae are represented by the greatest number of species, and are equally abundant in both epizoic and epiphytic habitats; the Haleciidae, Lafoeidae and Syntheciidae are epizoic, and Lineolariidae, with 1 species, epiphytic. The large plumose colonies of the Aglaopheniinae are epilithic. Hydroids are more abundant on the rough-water coastline, where red algae and the solitary ascidian, Herdmania momus (Savigny), are epiphytised by a large number of species. Delicate athecate species, and species of the Campanulariidae which may be expected to liberate medusae, are restricted to sheltered waters, or to depths below turbulence from surge in the rough-water locality. The high percentage of hydroids now known to be common to the coasts of South Australia, Tasmania and Victoria, supports the view that the Flindersian proyince extends from Bass Strait into the Great Australian Bight, PEARSON ISLAND EXPEDITION 1969+—9. HYDROIDS by JEANETTE E. WATSON* Summary =~ Warson, Jxanetre E. (1973)—Pearson Island Expedition 1969,—9, Hydroids. Trans. R, Sec, 8. Aust. 97(3)_ 153-200, 31 August 1973. Intensive collecting of the sublittoral hydroid fauna of Pearson Island in the Great Australian Bight, in January, 1969, yielded #1 species (with 3 varietics in one species), of which 13 species are newly described, There are 18 mew records for South Australia and 1 new record for Australia. The collection permits a fuller description of several hitherto poorly known southern Australian species, : Collections were made using SCUBA at 3 localities representative of environmental extremes on the coastline—a rough-water site expased to prevailing swell, a sheltered embay- ment, and a deep wuler situation in open ocean. The deeper water fauna contained species already known from deep dredgings in the Great Australian Bight, but differed markediy from the collection from shallower water. with only 1 species common to both, The Sertulariidae and Plumoulariidae are represented by the greatest number of species, and are cqually abundant in both epizoic and epiphytic habitats; the Haleciidae, Lafoeidae and Syntheciidae are epizoic, and Lineolariidae, with 1 species, epiphytic. The large plumose colonies of the Aglaopheniinae are epilithic. Hydroids ar¢ more abundant on the rough-water coustline, where ted algae and the solitary ascidian, Herdmania maomus (Savigny). are epiphytised by a large number of species. Delicate athecate species, und species of the Cam- panulariidac which may be expected lo liberate medusae, are restncted to sheltered waters. or to depths below turbulence from surge in the rough-water Jocality. The high percentage of hydroids now known to be common to the coasts of South Australia, ‘Tasmania and Victoria, supports ihe view that the Plindersian preyince extends from Bass Strait info the Great Australian Bight, Introduction Hydroids have been reported from a num- ber of expeditions around the southern and south-eastern Australian cOastlineé—the yoyage of the “Rattlesnake” (Busk 1852), the “Chal- lenger” dredgings in Bass Strait (Allman 1883, (884), the “Thetis” dredgings along the New South Wales coastline (Ritchie 1911). the “Findeyyour” expeditions from New South Wales to Western Australia (Bale 1914, 1915), the Michaelson-Hattmeyer Expedition to Western Australia (Stechow 1924, 1925}, and the McCoy Society Expeditions to Lady Julia Percy Island, Victoria (Blackburn 1937), and the Sir Joseph Banks Group, South Australia (Blackburn 1938). With the exception of the last two expeditions, the hydroid collections were made over a wide geographical area, while the collections of the Michaelson-Hart- meyet Expedition and the McCay Society Ex- peditions, although restricted in urea, were gained mainly fram drifi, the eulittoral zone, and to a minor extent, from shallow subtidal dredgings. No intensive survey has. however, been made of the subtidal hydroid fauna at any one locality in the Australian region, The joint expedition of the Department of Fisheries and Fauna Conservation of South Australia and the Royal Society of South Aus- tralia to Pearson I, 6-15 January, 1969, pro- vided an opportunity to undertake a compre- hensive subtidal survey of the hydroid fauna of an offshore island. “Honorary Associate, Invertebrate Zoology, National Museum of Victoria, Melbourne, Vic. 3000. + Other accounts of the geomorphology and biology of the Pearson Islands are given in Volume 95, Part 3 (4971) of the Transactions, as well as in the present part. 1%4 The South Australian hydroid fauna is known from reports of the ‘‘Endeavour™ dredgings in the Great Australian Bight along the 126° parallel of longitude, together with a small collection from the Isles of St. Francis in the Nuyts Archipelago, Blackburn (1938) recorded the shallow water fauna of the Sir Joseph Banks Group in Spencer Gulf, and Shepherd & Watson (1970) listed and dis- cussed the associations of hydroids and algac at West 1., Encounter Bay. The survey yielded a total of 81 species (with 3 varieties in one species), of which 13 species ate new; there are 18 new records for South Australia, including { new record for Australian waters. Only 2 athecale species were found, and 6 of the thecate hydroids could be identified only to genus. Pearson I. (Fig, 1) is:a graniuc island situ- ated ai Lat. 33°57'S, Long. 134°15'E. about — shelfered site roar he Eastern Cove Lang J34° 15'E Lot 33° 5a! go"s NORTH SECTION Harte wf aval SECTION 2 409 8 metres Fig. 1. Map of Pearson Island, showing study sites near the northern cnd. Inset shows the situation of Pearson Island in the Great Australian Bight. (After Shepherd & Womersley 1972). IRANETIE &, WALSON 64 kim offshore on the continental shelf in the eustern fegion of the Greut Australian Bight, Weatheritig of the granite has produced a rugged Lopography of massive blocks, cletts aud caverns, continnous to the seafloor at depths of 45 m immediately surrounding the island, with a rapid increase in depth offshore to 70 m. A more detiled account of the en- vironmental conditions is given by Shepherd & Womersley (1971), Methods Collections were mude by divers using SCUBA. As diving time was limited toa total of 30 hours underwater, two main sites were chosen for intensive collecting. One site wus on the rough-water windward, southwesterly side of the island; the other was in the more sheltered north facing Eastern Cove (Fig. 1), The benthic flora and fauna at each sile was systematically sampled (with particular atten- tion to hydroids) from the upper sublittoral 10 the seafloor at 50 m depth. Two additional small epllections were also made—one in sea- grass meadows in the more sheltered part of Exsiern Cove, und another, at 65 m depth, 4 km to the south, between Pearson 7. and Dorothee (Station F), Because of the rugged nature anc exposure of the coastline to surf, no collection of the intertidal fauna was made, Collections Holotype and paratype microslides, and other microstides and material are lodged jn the Nutional Museum of Victoria, Melbourne (NMY), Paratype microslides are also lodged in the South Australian Museum (SAM). In most instances, the synonymy of Rulph (1958, 196la.b, 1966) is adopted, and only pertinent references to species in Australian literature ure given. The status of several species is reviewed to tesalye confusion in the literature, and a number of rare and poorly known species ate redescribed, The site notation of Shepherd & Womersley (1971) is followed, “R” denoting material col- lected on the rough-water side of the island, and “S” denoting the sheltcred side. Hydroids collected in deep water at Stalion F are noted separatcly. Depths at which cach species was collected ure given. These depths will, how- ever, represent only part of the total range of each species. In most instances, the substrate upon which each species was found is ulso noted, As many hydroids ate hoth seasonal and irregular in occurrence, it is likely that collectiuns made at oiher parts of the island HYDROIDS or even at the same sites at other times, would yield a slightly different faunal list. The algal acology of these Pearson L. sites is described by Shepherd & Womersley (L971), who also list the algal species collected. Ecology Oceurrence af Hydroids The collection yielded a large number of species, in spite of the apparent paucity of the hydroid fauna on Arst inspection of the locality. Many of the species are crypuc forms growing sparscly In small colonies among algae, where only accessible with SCUBA. Even those species (Selanderia fusca, Thecocarpus divari- cates var. maccoyi, Aalicorearia longiroxtris, H. prafifera) which are known to form con- spicuous colonres in other localities, Were small and attenuated, suggesting that conditions for growth were not entirely favourable. This may be due to the strong surge conditions around the island preventing good grawth of the colonies, or to the high light transmittance of these waters, which appears to inhibit bydroid growth (J. W. unpublished data). The only athecate species, Tuhuleria larynx and Selanderia fuseu, recorded from Pearson I, were Found in relatively sheltered situations on the rough-water site. Only one colony of the former species, growing deep within a euvern, was recorded, whereas the Jarter spevics occurred as abundant small colonies in sheltered situations among the holdfasts of the brown kelp Ecklonia radiara. The scarcity in rough ocean waters. of athe- cate and other specics which liberate medusae has ulready been noted at West, I. (Shepherd & Watson 1970). Thua their absence from Pearson I. is not surprising, considering the exposure of the coastline to surf. Caripanu- faria wustealis, a species likely to liberate medusae, but whose reproductive strictures ure still unknown, was however common on the rough-water site, but only at a depth of 34-30 m, well below the zone of maximum turbulence, The collection from Station F, at 635 m depth, yielded a markedly different fauna from that of shallower water. The seafloor at this station was tippleanarked sand, with tare algae, a sparse epifauna of worm tubes, cal- caréous hryozou, solitary acidians, and ald shell. The dominant hydroids here were Syen- plectoscyphus subdichotomus, S. fongithecus, Syrtheciuin elegans £. subventricosumt and Plamularia axsymmetrica The only species of this group also fanging into shallower water 15 was S. slbdichoionius bit it Was uncommon, P. asyrumetricg, the most abundant species in the deeper water, has heen recorded only three times previously, from adjacent waters of the Great Australian Bight. Reiaionship berween Hydroid anid Subsinate Although little firm evidence of the associa- fon between hydroids and substrate can be gaincd on the hasis of ane series of collections, a mumber of broad relationships aud possible obligatory associutions are evident from the Peurson [. material. OF the total of &1 specres and 3 varieties, 27 urc exclusively epiphytic, 30 are non-cpiphytic, und 18 are both epiphytic and epizoic, The holdfast fauna, although strictly epiphytic, is listed with epizoic, epilithic and "{ceegrowing” species. (Table 3.) A. Bpiphytie Hydroids (Table 2). The two major families present, the Ser- tulariidae and the Plumulariidue, are almost equally divided between epiphytic and ¢pizoic species. The Lineolariidae,. represented only by Lineolaria spinulese, is epiphytic, Altogether, 47 species ate associated with red algac. mostly on the rough-water sile, 27 species are associy- ted with brown algue, and 3 species with green algue, This is tn accord with findings at West f. (Shepherd & Watson 1970) where red algae were alsa the most heavily epiphytised group. The most abuadant and widely distributed species of algae had the greatest number of hydroid epiphytes. Brown algae, particularly Sargassum, although a substrate for fewer hydroids, were often heavily epiphytsed by luxuriant colonies of some common apecies such as Amphishelia mininia var. pumiloides, Plumularia epibracteolosa and = Sertularella avrilia. Several hydroids showed a hich degree of selectivity and were ussociated with only ane algal substrate (Table 2}, but as these species Were not of common occurrence, it i uncer tain whether an obligatory relationship actually exists. However, there are two inslances of a commonly occurring hydroid associated with only one species of alga. Sertwaria acuta was found only on the red alga Stenoeliadia aus- tralix, whereas at West [. it wis abundantly associated with the red alga Piacelecarpus lahilfardier’. ‘The factors influencing the pref- erence of §. acura for Stenocludia atustralfy, to the exclusion of PRacerecarpus labitlardieri, at Pearson I. are unknown. The mast vonspicgtious assaciatinin Was thut of Plamualarte epibructeoiosa with Use brown ISG JEANETTE bE WALSON alea Sargassum bracreolosuin, The fronds of this alva were densely covered hy the hydroid, in contrast to the stems which were exclusively epiphytised by Amphishetia snininta vat. puniloides. S. bracteolosunr was also recorded at West |., but was epiphytised only by A, aint and Campanularia ausivaliv. Two other species, Lineolaria spinulose and Plorindaria dastralis, were common epiphytes tm the séagriss Posidonia australis, but were not associated with algae. Colonies of both hydroids were Frequently intergrown on, the same blade of seagrass. The growth habit of Phunuluria flexuosa with a species ol the ved algal genus M yehedea has not previously been reported, Usually hydroids avoid algae with aw thallus of small diameter (Nishihira 1967), The frond of Muochodee sp., although somewhat Jurger than the hydroid stolon, js nevertheless rather nar- row. Vhe hydroid stolon passes length wise in- letnally through the frond, giving off stems to the outer surface at regular intervals. Of particular interest is the gradational epiphylism displayed by the Arniphisbetia mininia-A, minuseule group, Bale (1884) dis- tinguished var. pumtiloides from, var. intermedia entirely upon the structures of the trophosome. Hoth these varieties, and the closely related species A. minusent, are abundant in the present collection, und display a marked gradational preference for certain groups of ulgae—the robust var, pumilaides is found on larec brown algac of the genus Sargassum (8. varjans, §. verruculosion, S. bracteolosumy and On Acrecerpia paniculaa; var. intermedia, a small Lorm, is assuciated with the red algae Rhodvinenia australis, Metamaytophera fabel- lata, Levrencia élata, and Carpopeltis pipvllo- Phord A, minuscula is both epiphytic and epi- zuic and is associated with the red alga Lavrea- cia elare, the brown alga Distromtium flabetle- tum, a species of the green alga Caulerpa, as well us being epizoie on Herdmania monnes and Aalicornaria longirosiris, B. Epizoic Hydroids The Lafocidac, Syntheciidae and Halectidae (with one exception Halecium sp. 1) are en- tirely eépizoic. Generally, epizoic associations are less well defined than epiphytic assacia- tions, most of the species involved being found on a wide variety of animal substrates, The substrates upon which hydroids: were found were, in order of abundance, other hydroids (19 oceurpences), culcureous bryozou (15), splines (4), the sulitary ascidian Herdnanig mommies (l4), compound aseidians (3). und muciliginous worm tubes. (2). Of the animal Substrates, only A. moms and other hydroids could be identified to species, The two species of hydroids most commanly enpizoitised by other hydroids are Thececarpas divaricatus var. eystifera and Halicormmaria longirastris, whose thick robust stems are sui able for colonisation by the small stolonic. species such as Syvaiplecroscyphus epizoicns, Retieularia antarctica and R. gsnulare, Herdmania rromus, one of the most ahun- dint larger invertebrates at Pearson I,, grows upon rock walls in open situations where there is modetale water movement. The leathery siphonal region of the ascidian is colonised by small species of red algae, bryozoans and hy- droids, the most commonly occurring hydroics being Sertulerelle robusta, Sertularella sp. 1, and Diphasia siebcar late. C. Epilithic Uydroids Epilithic colonies are usually conspicuous plumose forms growing from small matted routstovks wn rock surfaces in open situutions where they can take: maximum advantage of Water movement, This group, comprising Thecocarpuy divaricaus val, eystifera, Malicey- naria profifera, H. fonpiroyrris, and H. aurea, all belong ta the Aglsopheniinae, Closely allied in habit ta the true cpilithic species are the lwo “freegrowing™ plumularian species, Plumularia asymmetrica and Halop- teris xtleda. Both wre large plumose colonies growing from a small rootstock attached to pebbles or shell fragments buried in the seu- foor, D. Ner-selective Hydroids Species oceurring in both epizvic and epiphy- lic habitats are often also associated with the most ubunodyot animals ind plants, and are thus amoung the most commonly occurring hydroids, The most frequent of these multi- preferential associations arc: Hydeaied Sertularella rohusra Srebstrate Ballia callipricha Herdmania momus Cavreneta eluta Herdmania momus Amenysla pinneri fides Herdmania morass Sertutwrelia sp 1, Diphasia subcarinate ee ee ee Although many species (18) are both epi- zoic and epiphytic, only 2 species, Thecocarpus divericunsy and Halicarnaria longirostris are epilithic as well. The largest of the 3 varieties of FT. divuricetus, var. crstifera, is epilithic. HYDROIDS 157 while of the 2 smallee varieties, var, 5rigesi is pradational between epiphyde and epizoic, and var, macceyi is epiphytic. Distribution All thecate families, with the exception of the Campiunuliniidae, are represented in the collections. Campanulariidae are represented with 5 species, Sertulariidae with 31, Plumu- lariidae with 31, Halecitdae with 5, Lafoeidae with 4, Syntheciidie with 2, and Lincolanidac with | species With the exception of Thecocerpus divari- cutus var. drives’ (previously recorded trom New South Wales), ARericwaria antaretica (Western Australia), and Zygophylax anti- puhes (Torres: Strait), all other species newly recorded from South Australia are known trom Victorian waters, mostly from the intensive col- lecting of Mulder & Trebileack (1909-1916) along the central Victorian coustline, from Port Phillip Heads to Torquay, The new record for Australia, Syatheeiusa dentigerum, has been reported only twice pre- viously, once from the Indian Ocean, und once from South Africa. The genus Lyrocarpus, well known from the Indo-Pacific region, ts recorded for the first time (1, nuléer’) trom southern waters. Only 14 of the 38 species listed by Black- burn (1938) from the Sir Joseph Banks Ciroup were in the Pearson I, collections. The two groups of islands, however, are subject to dil- ferent environmental conditions, the former group of islands being situated in sheltered water at the southern end of Spencer Gulf, in contrast te the extreme exposure to rough water of Pearson I. in the Great Australian Bight. Comparison of the faunal lists of the twa island groups shows thal the species com- mon to both ure mostly specics epiphytic on algae, and on the seagrass Pasidenia casusiralts. Zoogeogruphy Of the 83 specics and 3 varictics recorded from Pearson |. 18 spectés are comnion to New Zealand waters, 15 have a northern Aus- tralian and western Indo-Pacific distribution, 10 specics occur jn South African waters, 6 are recorded from Japan, 2 from the Antarctic, and 2 are cosmopolitan. Thirty-nine (49%) of the species recorded (including the new species) ate, us presently known, cndemic to southern and south-eastern waters of Australia. Blackburn (1942) estimated that 42%. of the known hydroid Iouny of South Australia Tanged into New South Wales, and 189% into Western Australia, The present collection (with 1 variety common to N,S,W. and 2 species common to W. Aust.) does not substantially alter these estimates, The basis of comparison between the 3 States is. however, poor, as both the Jeep and shallow water hydroid fauna ot South Australia as now better known from SCUBA collections, whereas much of our knowledge of the hydroid fauna of New South Wales comes from deeper dredgings On the continental shelf, and that of Western Australia is from the reports of shallow water collections between Albany and Shark Bay (Stechow 1924, 1925). The 18 new records from the present colfec- tion, combined with 18 from West T, (Shep- herd & Watson 1970) brings the South Aus- tralian bydroid fauna, based on Blackburn's list, to 1 L9 species. Thus, the total number of species common to South Australia and Victoria is 81 (61%) of the knewn South Australian fauna, This fizure docs not differ greatly from Blackburn's earlier estimate of 65%, Based on Hodgson (1950), the fuuna com- mon to both South Australia and Tasmania ts 69% of the South Australian fauna. Che species common to Victoria and Tasmania comprises 70% of the known Tasmanian fauna. This distribution putlern lends further support to the contention of Womersley & Ed- monds (1958) that the Flindersian Province embraces much of the Maugean, anil exterils from the eastern Vicrorian coastline io at Irast the central coastline of South Austritia. Systematic Section Order ATHECATA Family TUBULARTIDAE Tobutaria larynx Ellis & Solander, 1786, 31, Bule, 1888: 748. Ralph, 1953: 68; 1966; 160. Reeords: R, 24 m, on walls of cavern, shel- tered from surge. Material: One small cluster of stems to 2 em high, Sven increasing gradually im diam, dis- tally ts OS em. Perisare thick, smooth, wilh groups of 3-8 annulalions; regrowth of broken stems bepinning with a new series of annula- tions. Hydranth 1.2 mm long, 1.0 mr wide, but tentacles not fully extended. Proximal whorl of tentacles a Jitthe longer tha clistul. Gonophores small, spherical, sex tideterminate, clustered between whorls of tentucies. Celoii— tentocles white, gonophores pink 158 JEANETTE E. WATSON TABLE 1 List of Species Substrate notation; EZ = epizoic, Ep = epiphytic, El = epilithic, Fg = freegrowing, Hf = holdfast fauna. Symbols are given In order of abundance of colonies on substrate, * denotes a new record for South Australia. . The number preceding names of the species in the following list is the key to the species in Tables 2 and ATHECATA Family TUBULARITIDAE 1. *Tubylaria larynx Ellis & Solander, El. Family SOLANDERIIDAE 2. Solanderia fusca (Gray). Hf, THECATA Family CAMPANULARIIDAE 3. Clytia (?) pearsonensis n.sp. Ez. 4. Campanularia ambiplica Mulder & Trebileock. Ep. 5. Campanularia australis Stechow. Ep, Ez. 6. *Campanuluria gaussica Stechow. Fz, 7. Campanularia sp. Ep. Family LAFOEIDAE 8. *Reticuluria entarctica (Hartlaub), Ez. 9. Reticularia annulata n.sp. Ez. 10. Reticularia sp, Ez. 11. *Zygophylax anfipathes (Lamarck). Hf. Family LINEOLARTIDAE 12. Linevlaria spinulosa Hincks. Ep. Family WALECUDAE 13, *Ophiodissa australis (Bale). Ep. 14, Ophoidissa blackburni nsp. Ez. 1S. Phylactotheca armata Stechow. Ez. 16. Halecium delicalulum Coughtrey. Ez. 17. Halecium sp. 1. Ez. 18. Halecium sp. 2. Ep. Family SYNTHECIIDAR 19, Synthecium elegans forma subventricosum Bale. Ez. 20. “Synthecium dentigerum Jarvis, Eu Family SERTULARIIDAE 21. Thyroscyphus marginatus (Bale). Ep, Ez. 22. Parascyphus simplex (Lamouroux), Ez. 23, Diphasia subcarinata (Rusk). Ep, Ez. 24. Stereotheca elongata (Lamouroux), Ep. 25. Crateritheca acanthostoma (Bale), Ep, Ez. 26, *Crateritheca crenata (Bale). Ep. 27. Sulucia obliquanoda (Mulder & Trebilcock), Ep, Ez. 28. Sertularella robusta Coughtrey, Ep, Ez. 29. *Sertilarella simplex (Hutton). Ez. 30. Sertularella annulaventricosa Mulder & Trebileock Ep, Ez. 31. Sertulareila avrilia n.sp- Ep. 32. Sertularella sp. 1. Ez, Ep, 33. Sertularella sp. 2. ? 34. *Symplectoxcyphus longithecus (Bale). ? 35. Symplectoscyphus subdichotomus (Kirchenpauer). Ez. 36. Symplectoscyphus neglectus (Thompson), Ep. 37, Symplectoscyphus indivisus (Bale). Ep. 38, Symplectoscyphus pygmaeus ?(Bale), Ez. 39. Symplectuscyphus macrothecus (Bale), Ep. 40. Symplectoscyphus rostratus n.sp. Ep, Ez. 41. Symplectoscyphus epizoicus n.sp. Ez. 42. Sertularia macrocarpa Bale. Hf. 43, Sertularia iinguicilata Busk, Ez, Hf. 44, *Sertularia bicuspidata Lamarck. Ep. 45, Sertularia maccallumi Bartlett, Ep. 46, Sertularia acuta Stechow, Ep. 47, Amphishetia maplestonei (Bale). Hf. 48. Amphisbetia pulchella (Thompson). Ep, Ez. 49, Amphisbetia elyeni n.sp, Fz, Ep, HYDROINS 159 50. Amplishetia minima var. pumiloides Bale, Ep, St. Amphixhetia minima var. intermedia Bale. Ep. Ez. 32. Amphishetia minuscula (Bale). Ep, Ez. Family PLUMULARTITDAK 33. Pyenotheea producta (Bale). Ep. 54. *Amtennella tubulosa (Bale). Ep “Antennella campuniliformis (Mulder & Trebilcock). Ep. 56. *Antennella secundaria s.sp, dubiafermis (Mulder & Trebilcack ), Ep, 37. Halopteris suleata (Lamarck). Fe. 38, Halopteris campanila var. campanula (Busk). El, 59. Halapteris biuski (Bale), Fz. 60. Halopteriy oppasita (Mulder & Trebileack). Ep. 61. *Gaitva bale (Bartlett). Ep. 62. Gattya uglaopheniaformis (Mulder & Trebilcock). Ez, Ep. 63. Gaftya trebileovki nusp. Ep. 64. Plumularia procumbens Spencer. Fl. 65. Plumularia asymmetrica Bale, Fg. 66. Plumutaria flecnosa Bale. Ep. 67. Plumularia spinnlosa Bale, Ep. Ez. 68. *Plumularia goldsteini Bale. Ep. 69. Plumularia obliqua (Johnston). Ep. 70, Plumularia australis Kirchenpaver. Ep. 71, Plumutaria epibractealosa n.sp, Ep. 72. Plumularia meretricia asp. Ez. 73. Plurmitlaria togata n.sp. Ep. 74, Plimularia australiensis n.sp. Ez, 75, Aglaophenia plumosa Bale. Fz, Ep. 76. Thecocarpus divaricatiis yar. maccayi Bale, Fp. 77. *Thecocarpus divaricatus var. brigest Bale. Ep, Ez. 78. Theeocarpus divaricutys var. cystifera Bale. Fl. 79. *Lyvtocarpus mulderi (Rartlett). ? 80. Malicarnopsis elegans (Lamarck). E}. 81. Halicornaria longirastris (Kirchenpauer). FJ, Ez, Ep. 82. *Halicornaria prolifera Bale. El. 83. Halivernaria aurea np. EL Remarks; This cosmopolitan species was douht- fully recorded for the first time from Austra- lian waters by Ralph (1966) who reported a few infertile stems from Port Phillip Bay, Vic, This is the second tecord of the species in Aus- tralia, and a new record for S. Aust. Solanderia fuseq (Gray, 1868). Watson é& Uti- nomi, 1971; 19, pl. 8. Ceratella fusca (Gray), Spencer, 18915 &- Records: R, 14-33 m, among holdfasts of brown algac. Material: Four very small infertile colonies broken off from the rootstock, the largest colony 5S mm high and 20 mm _ wide. Colonics compact. branching closely in one plane from a thick main stem, Srem of largest colony 3 mm wide at base, stem and branches flattened in plane of growth. Aydrophores are Open shelf-like structures, prominent on younger branches, edged with 10-15: bluntly pointed terminal spines connected by a thick. shallowly scalloped chitinous web. Trabecilate meshwork of branches close and solid, with square to circular openings, Spires similar to those edging hydrophore developed at points of intersection of meshwork on older branches. iTvdranuths poorly preserved. Colour—stems dark brown, shading to ight brown on grow- ing tips. Remarks: The colonies of §. fitsce from Pear- son J., although dwarfed and infertile, are mature, occurring among algae on horizontal rack faces. This. is in contrast to the known habitat of larger specimens from Victorian waters, which seem to favour vertical walls and the interior of caverns (J.W., unpub- lished). Bale (1888, p. 749) mentions that his small colonies from Sydney were from “Lamin- aria roots” (probably Ecklonia radiata hold- fasts). Watson & Utinomi (1971). reported that the spinous trabeculae were not present in material examined by them from the Great Australian Bight, vet the Pearson J. specimens show these spines clearly. Unknown environ- mental and geographical factors may thus in- fluence structural variations within the species. Order THECATA Family CAMPANULARIIDAE Clytia (’) pearsonensis n.sp_ FIG. 2 160 JEANETTE E. WATSON TABLE 2 Fpiphyic Hydroiils The numbers tefer to the species as given in the species list. VC = very common, C = common, R = rare, Aleal Substrate Hydroid CHLOROPHYTA Canlerpa brownii (C.Ag.) Endlicher. 63(R) Cailerpa staplicinsenle (Turner) J. Agardh. T7(R) Caulerpa sp. 52(VC) PHAEQPHYTA Disrominm flabellaium Womersley. §2(VC), 53(R), 56(R) Distramium sp. 37(C) Zonaria spiralis J. Agardh. Ta(VOY Sevtotlalia darvcarpea (Turn.) Greville. 24(VC) Acrocarpia paniculala (Turn) Areschoug. 24(VC), 39(R), S0(VC), 76(VC) Cystephora brownii (Turn, ) J, Agardh, 5(C) Sargassum verruculosum (Mert-) I Agardh. 31(C), 40(C). 60(R) Sargassum hractéolesum J. Agardh. S0(VC),7I(VC) Sargassum spinuligerum Sonder, Sargassum Varians Sonder. Sargassum 8D, RHODOPHYTA | Delisea pulehra (Grev.) Montagne. Preracladia lucida (R.Br.) J. Agardh. Rhodopeltis anstealis Harvey. Metazoniolithon chargides (Lamx.) W. v. Bosse. Metamasiophara flabellata (Sond.) Setchell, Carpopeltis phyllophara (A. & A.) Schmitz. Callopha lis caccinea Harvey. Plocamium aneastune (J, Agardh) Hooker & Harvey. Hacamium cartilagineum (L.) Dixon. Phacelocarpus labillardieri (Mert.) J. Agardh, Stvenoclacdia australis (Sond.) Silva. Alvehodea sp, Rhoadymenia anusiratis Sonder. Ballia callitricha (C.Ag,) Kuetzing. Prerosiphonia? Anunsia pinnatifida Harvey. Laurencia clata (C.Ag.) Harvey. Inidentified red algac. ANGIOSPERMAE Pasidonia australis Hook. f. 37(C), 50(VC), 60(R) sa.VC), 55(R) 21(R), 30(C), 36(VC), I7(C), S4ER), 69(R) 48(R) 5(C), 36(VC), 45(VC). 48(R), 55(CY 61(C) 44(R) 27(VC), 36(VC), 73°VC) 44(R), SICVC), 61(C), 69(R), T6(VCO) 45(VC). 75(R) 62(R) 67(C) 7T6(VC) 24(VC) 24(VC), 46(VC) 66(R) SI(VC), 56(C) 28(C) 61(C) 23(VC) 32(VC), Si¢VC), S52°VC), SS(C), 67(C) 4(R), 70K), 25(R). 27 (VE), 30(€). 36(VC). 40(R), 49(C), 53(R), T7(R), STC VO) 12(VC), TOCVE) 37(C), Type Material and Records; Holotype, NMYV G1914, microslide—R, 22 m, on stem of Thececarpus divaricatis var. cystifere; paratype, G1915, microslide—R, 34 m, on bryozoa. Description from holotype and paratype: Pedi- cels long, of variable diametcr. irregularly wrinkled or smooth (holotype shows indistiact distal annulations), arising from a creeping stolon. Hydratheede large, cylindrical. walls smooth, perisarc very thin and delicate, mar- vin entire. everted into a thin lip. Thecal wall slightly thickened proximally, hydrotheca with- out floor, tapering inta pedicel, a trace of a very thin diaphragm near base. Hvdranth too poorly preserved for diagnosis, Ganotheca ab- sent, Remarks: Only 2 undamaged hydrothecae were found im the entire collection, although othet's, badly damaged, were noted. It is possible that the species has previously been overlooked hecause of the extremely delicate nature of the perisare, which collapses immediately on re- moval from water. C. pearsonensiy ts closely related ta Lao- medea michael-sarsi Léloup, 1935, reported from only two localities—the West Indies, and the west coast of North Africa. The hydro- theca of L. michael-sarsi are, however, shorter and less than half the diameter of C. pearsonensis. (Measurements ate given for camparison), Following Millard (1959, p. 248), the species may be referable to cither Campatu- HYDROIDS 161 TABLE 3 Epizoic, Epilithic, Freegrowing and Holdfast Associations. Substrate Wydroid Epizoic Species Ascidian— . Herdmania momus (Savigny) Compeund ascidians Sponge Calcareous bryozoa Worm tubes Other Hydroids— Synthecium sp. Thyroscyphus marginatus (Bale), Sertilaria unguicilata Busk. Symplectoscyphus subdichotomus (Kirchenpauer ). Halopteris campanila var. campanula (Busk), Plurnularia proeuntbens Spencer. Thececarpus. divaricatus var. cystifera Bale. Halicornaria longirastris (Kirchenpauer). Epilithic Species Freeerowing Species Tloldfast Species Cc. pearsonensis 1.. anichael-sarsi Yi Ww. halo nara * A Dinension, mm tyre type Africa Tndies Stem length 1.80 1.32 = 1.00-1,50 dium. 007 017 _ O.1-0.15 Hydrotheca— Width af margin 0.58 O68 0.25 0.25-0,30 0.69 O65 0.40 0,50 depth to diaphrasta O78 laria or Clytia. The barely discernible dia- phragm and very delicate thecal wall suggest it may belong to the latter genus, but its system- atic position is indeterminate until fertile material is found. Campanularia ambiplica Mulder & Trebilcock, 1914: 11, figs, 2-4, Shepherd & Watson, 1970: 140. Paracalix ambiplica (M. & T.). Stechow, 1925: 209, fig. EB. Recards: S, 5—14 m, on red algae Material: Three infertile stems. Stems short, spirally annulated. Hydrothecae long, narrow, walls parallel, a very strong S-shaped fold about halfway along thecal wall. Margin with 6 teeth, cach with several reduplications. Remarks: Type material of C. ambiplica in the collection of the NMV shows more campanu- late hydrothecue with blunter and less deeply excavated marginal teeth than the Pearson I. 14(C), 16(C), 19(R), 20(R), 21(R), 22(R), 23(VC), 2B(VC), 29(R). 32°VE). 3R(C); 43(R), 49(C). 59(R) 15(R), 38(C), 75(R) 5(C}, 9(R). 13(R), 14(C), 15(R), 25¢R), 27(C), 28(VC), 38(C), 49°VC), 56(C), §9(R), 74(C), 72(R) 3(R), 6(R), 10(R). 14(G), 27(C), 2B(VCd, 29(R}, 30(C), 32(VC), 35(R), 38(C), 40(R). 59(R), 75(R). BLEVC) 19(R), 59(R) 16(C) 67(C) 20(R), 56(C) TT(RY 32(C) 16(C), 62(C) 3(R), B(VC), 19(R), 22(R), 29(R), 38(C), 4i(C) 8(VC), 17(R), 41(C), 520VC) 1(R). 58(R), 64(C), 7R(C), BOR), BICVC). 82(R), 83(C) S7(C), 65 (VC) 2(@), 11(R), 42(C), 4300), 47(C) specimens. Stechow's figures of specimens from Champion Bay, W. Aust. aré intermediate in length between the two. Meussurements are given for comparison. Victoria Diwensions, nm Peai3on L. Champion Bay (M. & T) Stem diam. 0.06 0,06 0.06 Hydrotkeca— fongth 1,52 0.42 0.34 width DAT O18 0.17 Campanularia australis Stechow, 1924: 61. Shepherd & Watson, 1970: 140. Orthopytis australis (Stechaw). Hirohito, 1969: 10, fig. 9. Records: R, 34m, on the algae Pteracladia lucie, Cysiophora brownii, and sponge. Material: Stems variable, to 3 mm tong, longer slems smooth, short stems annulated, Aydro- thecae compressed, with a wide submarginal flange and 9-10 blunily pointed teeth, in one instance showing reduplication. Aydranih with 16—20. tentacles, Colonies fertile. Remarks: Although widely distributed at all depths and on a variety of substrates, the colonies were. not luxuriant. 162 Caumpantilings 1924; 62, guussica Stechow, 1923: 102; FIG, 3 Record: S24 m, on calewrcous bryazoa- Miverial: Three infertile stems, Sremes to 4 rom long, shewing jomts where breaks have fe- generiuled, A spherule between stem and bydro- theea. Hydretheeae large, campanulate, 1.26- 1,32 mm deep, expanding evenly from a nar- row base to margin, an annular diaphragm in thecal cavity. Margin variable in diam., 0.78— 1.2 mm, with 12 deep tongue-shaped teeth 0.015-0.618 mm wide at base, 0.013-0.015 mm long, the sinus hetween of same shupe and size as tooth. Aydranth with approx. 16 ten- tacles surrounding a thick annular hypostome, similar to that of Eiclenedr/um, Remarks; The Pearson J, specimens are among the largest specimens of Campanularia recorded from Ausiralian waters, the only other specimen of comparable size being “Campanu- lavia tinera var." of Mulder & Trebileock (19149). from Brey Creek, Vic, (see dis- cussion below), This is a new record for S. Aust. Remarks on whe states of Co tinela Hineky, 1867, C, giussica, and C. australis, Stechow (1925, p, 206) placed Mulder & Trebileock’s vars. ‘“‘a", “b", “co” snd “a” of C. tineta in tentative synonymy with C. peur sica, However, the dimensions of the hydrothe- coe calculated from Mulder & Trebilcock's figures are somewhat greater than Lhose given by Stechow for his specimens. Moreover, his figure does net show the annular diaphragm figured by Mulder & Trebilcock, a feature alo presentin the Pearson T. specimens. Earlier, Stechow (1924) stated that the gonosame of CG. gaussica was unknown, yet in- cluded in his synonymy (1923, p. 102) a questionuble reference to the C. tincra of Bale (1884, p. 57) from Portland, Victoria, for which the ponutheca was figured. He later te- ferred Bale’s species ta C, langitheca without explanation. The Portland specimen ih the col- lection of the NMV is undouhtedly C, australis, nul C. gansefew. T cjinnot agree with Rees & Thursficld (1965, p. 94) who reterted ©. gansyica to the synonymy of G. dincta, The latter is a very smal) and distinctive species; although they stated they had examined the type material of C. iieta, they failed to ote the very con- siderable difference in size between the two. The definition of the Four species, C) zincrer, C, ausrralis, C. gatssiea and C, africatia, from IEANETTE FE. WATSON Austratian waters rs thus somewhat confused, Although €, tiara and C. australis are very similar, with bilaterally symmetries! hydro- thecae, C’, ansrralis ts considerably the larger of the two. ©. dugfralis shows a wide choice of substrite, being bolh epizoic and epiphytic, whereas C. tinete appeurs to be most Frequently assochited with the seagrass Amphibolls antarc- tica LW, unpublished), Wirohity (1969, p. 10) transferred C. any- tralis to Orthapyxts on the basis of the bilateral symmetry of the hydrotheca, but the true gencric status of C. australiy will remain inde- terminate until the gonosome. is found. C. africana is a distinct species, and has been redescribed by Millard (1966, p, 474), The hydrotheca is of medium size and the gonosome is known. This species. has been re- corded from Queensland (Pennycuick 1959, pp. 169), from “rock poals and weed”, Uniil the collection of fertile material estab- lishes the validity of C, waswralis and C, gays- vica, those forms from Australian waters with very large campanulaie hydrothecae and 10-14 tongne-shaped teeth are recognized as (". guus- sie, those with large parallel-walled hydro- theeae and bilateral symmetry are recognized as C. austrafis, and those similar to C. atastralis but much smaller in size, as C, tinere. In the gase of C_ gaitssica, it is possible that more than One species may actually be involved, Campanularia sp- FIG. 4 Records; S, 17-20 m. on red atgac. Mfarerial: Three infertile stems. Srems 0.51— 1,72 mm long, spirally annulated, annulations sometimes indistinct, maximum width of stem, 04 mm. Aydrothecae campanulate, length 0.39 mm, widest about one third distance up from base, this point belng marked by a crumpled fold encircling thecal wall. Base of hydrotheea flat, with o slight concavity, a socket and xpherule between hydrotheca and stem. Margin 0.22 mm in diam, with & hroad fongue-shoped teeth 0.025 mm high; width be- tween tecth, 0.06 mm. Remarks; The hydrotheeac are very delicate, Although the hydrolthecae are somewhat col- lapsed in mounting, the fold around the proxi- mal region of the thecgl wall is clear in all specimens, The specimens are undoubledly referable to the C. ambiplica-C. pulechratheca group en- demic ta southern Australian waters, most resembling the latter species, However, ©, IL¥YDROIDS 163 Reticularia annulgfa nsp, Fig, 5—Group of three hydrothecac Fig. 6,—Distal chd of Fig. 2 Clytia (?) pearsonensis n.sp. Hydrotheca, from holotype. Fig. 3- Campanuluria ganssica Stechow. Hydrotheca; stem with regenerated pedicel, Fig. 4, Campanularia sp. Hydrotheca. Figs. 5, hydrotheca, enlarged. Drawn from holotype. Figs. 7 6 .8. Reticularia sp. Fig. 7.—Part of colony, showing growth habit on bryozoan colony. Fig. 8 —Hydrotheca, enlarged, showing reyenerated distal end. pulchratheca has 14 sharply pointed teeth, the intrathecal fold is in the distal region, and does not encircle the thecal wall as in the present material. This may be a new species, but the material is inadequate for determina- tion. Family LAFOEIDAE Reticularia antarctica (Hartlaub, 1904). Tot- ton, 1930: 160, fly. 17, Briggs, 1938: 26. Eafoas antarcti¢a Hartlanb, 1904; 11, pl. 2, fig. Filellum 1925: 214. Recards: R, 18-33 m, on stem of Thecoeer- pus divaricatus var. cystiferu. S. 14 m, on stem of Halicarnaria longirostris. antarcticum {Hlartlauh). Stechow, Materia/: Luxuriant infertile colonies, Hydro- thecae delicate, of variable length, arising at various ungles from hydrorhiza so thickly that it is difficult to determine the length of the adnate part, but it is usually not more than one quarter of the total length of the hydro- theea. Margin slightly everted, often with 2-3 teduplications; occasionally an earlier redupli- cation about halfway along hydrotheca coin- cides with a slight flexure of the thecal wall. Length of free part of hydrotheca, including reduplications, 1.0-1,18 mm; diam. at margin, 0.21 mm. Remurks: Mt is very difficult to distinguish be- tween R. antarctica and R, serpens in the |i absence of coppiniac, and as the diameter of the (hecal margin is greater than those measure- ments given by Stechow (1925, p. 214) for R, serpens (after Millard 1958, p. 175), the Peur- son |, spccimens are referred to R. antarctica, This is the first record of R. antaretica from S. Aust. waters. (Other locality—W, Aust.) Reticolatia annulata n.sp, FIGS. 5. 6 Type Material una Records: Holotype NMV G1922, microslide: G2091, preserved Malerial, remuinder of holotype colony—sS, L7.m, on a small calcareous bryozoa. Description from holotype: Hydrothecae bong, tubular, inereasing slightly in diameter disttlly, adnate for a sroall part of length, free pari 0.15-0.18 mm, curving out from hydrorhiza, Hydrorecae ringed throughout eatire fength with closely und evenly spaced annular ribs, average distance between ribs U-US mm, each rib with shatply everted rim; unnulations on adgauline wall not as shatply defined us those on free wall, Margin circulur, entire, same diam. as hydrotheca, 0.19-0.26 mm, occtasion- ally sinucusly curved, with everted tim. Gono- theca wbsent, Remarks; R. annntata is closely related to both R. antarctica {Wartlaub, 1904) and R. serpens (Hassall, 1848) jn shape and dimensions of the hydrotheca, but it is easily distinguished from these species by the close thecyl rings, FR, serrata (Clarke, 1879) Is annulated, but the wnnulations are confined to the adnale part of the hydrotheca, and it is 4 much smaller species. The rings in R, canulatea are o£ uniform size, and the distance between them varies. litte along the entire length of the hydrotheca. They have developed by continuous apical reduplica- tion during growth of the hydrotheca, the flange of each rth being a relict margin. Reticufaria sp. FIGS. 7, 8 Recerd: R, [S m, colony investing stalk of calcareous bryozona, Materiel; One infertile cdlony. Hydrethecue arising in groups, or singly at irregular inter- vals, Hydrothecac from the outer hydrorhizal tubes adnate for approximately half their length, free part standing, out almost perpen- dicular to hydrorhiza. Length of free part 0.45— 0.66 mm, only the orifice of those hydrothecue more deeply embedded in the stolonic camplex visible. Hydrothecac tubular, 0.2 mm in diam,, IEANETTE, E. WATSON many with Z—3 regeneractions after breakage. some with marginal reduplication. Cole.e— brown. Remarks: The general appearance of the hydrothecae and the diameter of the margin ure very similar to R. antarctica from Pearson L., but the hydrothecae of the present specimens are much shorter; the thick woody fascicled hydrorhizal tubes further distinguish the present material. The twiggy appearance of the colony, iin- parted by the shape of the host, strongly sug- gesis the growth habit of Cryprolaria, but with- out the regularity of arrangement of the hydro- thecne of that genus. This may prove to be a new species Zygophylax antipathes (Lamarck, 1816). Rees & Thursfield, 1965: 76. Sermilaria antipauthes Lamarck, 1Bl6: 11S, Campandlaria rufa Bale, 1884: 54, pl. 1, fig. 1. Efesoneiia antipaties (Lamarck), Ritchie, 1910; Zygophylax rufa Bole, 1914¢: 90, FIG, 9 Records: R. 18-45 m, among holdfasts of hrown algue on vertical walls and on the seafloor. Muarevieal: Three infertile colonies, the largest 12 em high, growing from a small rootstock, Stew woody, very brittle, main stem fascicled (2 mm thick in largest colony) the fasciculu- tions decreasing distally along the branches. Branches given off randomly around main stem. some of younger branches mono- siphonic, /lydrothecae alternate, 0,32-0,34 may deep (margin to diaphragm) arising from an upoaphysis at 45° to stem, frequently a short segment (a broken und regenerated pedicel of an earlier hydrotheca). between Nycdrothecul pedicel and apophysis, Adcauline thecal wall convex, 0.30-0.37 mm long, usually smooth, sometimes. a little undulated; abcauline wall straight or slightly concave, 0,30+0,36 mm long. Margin usually with a distinctly everted rim 0.17 movin diam., occasionally with | re- duplication, Diaphragm near base of hydro- theca transverse, occasionally oblique. Nemiato- thecae pare, only 2 seen in mounted specimens, one given off from a hydrothecal apophysis, the ather from a polysiphonic tube of the stem. Colour—aeep reddish brown, Remarks; The branches are overgrown with algae and conipound ascidian, Bile (1914¢) maintained the distinction between Z. rufa and 2, antipathes on the fal- lowing cntenas HYDROIDS (i) the smaller colonies of Z. rufa, the lack of rigidity of the branches, and, Hid L. antipathes, following Billard, shows no distal narrowing of the hydrotheca, nor an everted margin. Examination of a series of microslides of Z, ea in the collection of the NMV, show. Bule’s material to have come from either a broken branch, or the distal end of a very young colony, and there ate few hydrothecae which are not hoticably narrowed distally; some also lack an everted margin. One branch of the Pearson L material bas a series of hydrothecse with almast straight walls, no eversion of the margin, und a rather more delicate perisarc than usual, Regenerated hydrothecal pedicels with an additional segment are common in the older regions of the stems, but are net present in the Younger branches. They are a character de- veloped with aging of the stem, and are thus not specifically diagnostic. I have compared microslides of Ritchie's “Thetis” material of Lictorelle artipathes with Z. rufa of Bale, and find them to be identical in all respects, except that the perisare of Z. rufa is much more delicate than that of the “Thetis” specimens. Ritchie did not comment on the presence of nematothecae (similur to those on the Pearson I. specimens) visible in his slides. These were apparently noted by Rees & Thursfield (1965) who transferred the species 10 Zygopliylex without comment. Since the present material has features which clearly bridge the gap between Z. rufa and Z. antpathes, the Wwo are considered synonymous, This is the first record of Z. aniipathes in S. Aust. waters. (Other localities—Torres Strait, and off Port Jackson, N.S.W.) Family LINEOLARIIDAE Lingokwia spinulosa Hincks, 1861: 280, pl. 8, Shepherd & Watson, 1970: 140. Record: S, 15 m, on the seagrass Posidenia ruasrrialts, Material; Numerous infertile colonies over- Tunning the blades of the seagrass. Remarks: L, spintlose was not found on any other substrate at Pearson L, Family HALECUDAR Ophiodissa austratis (Bale, 1919). ph renles avairaliy Bale, 1919- 396, pl. 16, fig. Record: R, 19 mi, On black sponge. 165 Material: One colony of several infertile stems growing from a matted hydrorhiza on the sur- fuce of the sponge, Sremx to 2 cm long, fas- cicled, itregularly branched, with 2-3 supple- mentary tubes extending two thirds the distonce up stem. Aydraphore with a few reduplica- tions. WNematothecae rare. Crleour—light greenish, with black patches scattered through- out hydrocaulus. (Under the microscope these pitches are black granules concentrated on the hydranth and in the coenosyre.) Remarks: The status of Ophiodissa haa been briefly discussed by Watson (1969, p, LIN), Bale (1919) described, but did noe figure the gonophore of O. australis, Ralph (1953, p, 342) way. uncertain whether @. australis is a synonym of Hydrodendroy — cacinifarmis (Ritchie, 1907) but kept the two apecies separate because “the hydrothecae of 4, aus- tralix Bule are shallower, measured fromm the margin to puncta line, than those of H. cuvini- formis, und the goncthecae of the latter are unknown". Millard (1966b, p. 490) described the gonophore of H, caciniformis fiom material from the Vema Seamount. off the west coast of South Africa. There are two microslides of O. australis in the Bale collection In NMV, one trom Green Point, N.S.W,, and the other from Port Phillip Heads. Vic. The latter specimen is 4 lightly fascicled stem 2 cm long, with u group of 10 male gonophores growing {rom the hydrohiza, and is undoubtedly the slide fram which Bale described the gonotheca of the species. The gonothecae aye smooth or very slightly wnnulated, with curved or straight pedicels, and several have a slight constriction just below ihe truncated distal end, The gonopheres are nearly mature, the blastostyle almest filling the gonothecal cavity, aod above the blasroscyle there ts a ring of black granules, The gonothecae and gonophores of Bale’s material are similar to those of A, caciniformis figured hy Millard, but the ponotheca of O.. australis is much longer and more than twice the width of those of JT. caciniforinis, Further- more, the hydraphote of HW. cacinifprmiy (trom Millard’s figure) is both wider and deeper than that of Q. ausiralixs from Green Point, It seems that the two species, while very similar, are distinct, Comparison of measurements (see helaw) of HH, caciniformis from New Zealand with Bale's Q. australfe shows that the New Zea- land maternal Falls near the dimensional range of OO. aeuwealls, and may well be this species. Lob JEASETTE, E, WATSON The finding of fertile material in New Zealand waters will settle this. point. O. australis Dimensions, mm H. caciniforialy Pearson Grein N: 8. I, Pi. Fealand = Africa Uycirophore— . diam, 1 Paneta dine 0.14 0.15 0,12 0.20 depth, margin to puacta ne 0.025 O05 0.44-4,06 0.10 Gonotheca length t.441.50 — 6 90-1,90 width at mporpyre — 0.94-1.00 —_ 0.40 The specimens from Pearson I. are identical im every respect with Bale’s 0. australis. This is the first record of O. awsrralis from §. Aust. Ophiodissa blackburni a.sp. FIGS, 10-12 Type Material and Records: Hoaletype. NMV G1927, microslide; G2092, preserved material, remuinder of holotype colony—-S, 27 m, on Herdinuiia monus; Paratypes GI928, G1929, microslides; G2093, pre- served material, reémuinder of paralype colony—S, 24-27 m, on bryozoa and sponge. Description from holatype ard paratypes: Hydrorhiza a winding tubular stolon 0,11-0,13 mm in diam,, thick and strongly corrugated throughout entire length, becoming erect at intervals 10 form monosiphonic stems. to 12 mm high, Uydrephores given off irregularly, either directly from the siolon or from stem, Pediccl of hydrophores of variable length, 0.19-0,27 mm, beginning with an annular con- striction 0,07-0,10 mm in diam., followed by 1-2 annulations, then expanding evenly to: mar- gin, Perisarc thin. Secondary and tertinr'y hydrophores common, branching outwards just below the diaphragm ot primary (or secon- dary) hydrophore, becoming ascending at an- nular constriction. Hydrophores: redupliculed up to 4 times; reduplications of variable length, given off successively from the diaphragm of preceding hydrophore, Diaphragm 0.13-0.17 mim in diam., moderately deep, 0.04 mm from margin (best seen in preserved material). Afur- vin flaring, with strongly everted lip, diam, 0.22-0.24 mm. Neutothecae sparse low tubu- lar orifices 0.03 mm high, and 0,05 mm in diam, at base, situated on hydrorhiza or stem, opposite, or nearly opposite hydrothecal pedi- ecl. Aydranth large, extensile, with approx. 30 stubby tentacles. Co/lawr—yellow, Gonetheca— absent. Remarks; The presence of nematothecae places the present material in Ophiodissa (Watson 1969, p. 111). Although in. some instances the hematothecae may be mistaken for the broken hase Of a hydrothecul pedicel, their position opposite the pedicel, and their smaller size usually serves to distinguish them. O. blackburni shows some resemblance to O. carrugata Praser, 1936, However, neither branching nor reduplication of the margin is mentioned or fizured by Fraser, and the ten- ticular orguns of O. currugata are described as being relatively large and flaring slightly at the marfgin (Fraser 1936, p, 113). Blackburn (1938, p, 322) described a frag- mentary Haleciunt sp. Crom the Jittoral zone of Reeyesby L in the Sir Joscph Banks Group. S. Aust., remarking that the material, too ob- scured by forcign matter for diagnosis, Was probably a new species, similar to A. corra- garuen Nutting, 1912. Although Hlackburn's specimens are not available for comparison, it is certain that his milerial aimel the present specimens are the same species. Phylactotheca armata Stechow, 1924: 54: 1925; 204, fiz. C. Blackhurn, (942° LOA, Ophtiodiata Jrogitts Blackburn, 1937a! 365, fig. Records; R, 33 m, on sponge and ascidian, Maserial: A few infertile stems to | em high. Renuirks; The Pearson I. material conforms to the description of the species given by Stechow and Blackburn. There are no secondary hydrophores, nor any nematothecac developed in the present material, Blackburn's specimens from Balnar- ring. Vie., similarly showed no sign of nemu- iothecac, Hence their presence or absence cam not be taken as a good diagnostic character lor Lhe aenus, Halecium delicatulum Coughtrey, 1876: 299, Ralph, 1958: 334, figs. 11, 12. (syno- nymy), Records: R, 21-45 m, on Plamularia pro- cemberns and Syntheciunt sp.; 8, 24 m, on Herdmania momus, and brvozoa, Material: Miny small infertile stems to 2 om high. Sresns irregularly and sparsely branched, a few are lightly fascicled, with an extra poly- siphonic tube running up the proximal part of the stem. Renuirkay Oye of the mest abundant epizoic species tm the collection, HYDROIDS UG7 Halecium sp. 1. FIG, 13 Record: R, 30 m, an lower stem of Halj- cernarie fongirostris, Moreelul’ A single infertile stem L2 mm high. Stem unfascicled, irregularly branched; stem and branch intemodes of vanable length, up to 0.22 mm, and 6,04 mm in diam., annulated proximally, but otherwise fairly amooth- Branches given off from distal end of inter- nodes on lower part of stem, Pedicel of pri- mary hydrephore of yariable length, proximal node transverse, follawed by 1-2 antulations, the remainder smooth, expanding evenly to diaphragm. Aydrophere small, shallow, with circular margin, 0.08-0.12.mm in diam., and strongly everted tim; up to 3 reduplications given off successively from mouth of preceding hydrophore. Diaphragm present, depth from margin to diaphragm, 0.02-0.03 mm. Secearn- dary and tertiary branches comman, arising from distal end of pedicel of primary (or secondary) hydrophore, Remarks: This very small form resembles H. tenelliom Hineks, 184) in size and delicacy of the trophasome, btit the dimensions are ever smalfer than those given by Millard (1957, p. 193) and Rilph (1958, p, 340) for this species. in the present material, only the first inter- node can be described as a true stem, the branching being truly arborescent, all sub- sequent internodes being secondary branches given off the pedicels of the primary hydro- phores. The presence or absence of punctae cannot be ascertained because of foreign mat- ter, However, the Bale collection in the NMV contains a microslide labelled “Halecium, Grif- fiths Point, July, 1880" with one small infertile stem identical with the Pearson J, specimen, and the hydrophores of this stem show « very clear rung of punctae between the margin and diaphragm. This is probably a new species, but due to ils similarity to HW. ¢enellam its identity is in- determinate until adequate Fertile material is found. Halecium sp. 2. FIG. 14 Record: R, 35 m, on algae, Murerial> Two yery small infertile stems. Aydrerhize tubular. Stents unbranched, 2 mm long, internodes of variable length, 0,28-0.66 rom, dian U.08-0,12 mm, perisare thick, divided into segments by 2-3 deep, transverse constrictions, the last segment expanding slightly to support base of hydrophore. Hydre- phore very shallow, depth to diaphragm 0,03 mm. Margin circular, 0.14-0:17 mm in diam., slishtly everted. Succeeding stem internodes arising just below hydrophore, standing out perpendictilarly, giving siem a zig zug appear- ance. Hydranth too large to retract into hydro- phore, body thick, about 24 stubby tentacles, Remarks: All the bydrathecal margins are so damaged that it is impossible to determine if punctae are present, Although the dimensions fall well within the range of J. lartkesteri (Bourne, 1890) (Millard 1968, p, 257) the internodes show no tendency to curve upward, nor is there any sign of the secondary hydro- phores common in this species. For these rea- sons, the present specimens are not assizned to A, fankestert. Family SYNTHECIIDAE Svyothecium elegans forma subveniricasum Bale, 7914, Ralph, 1958: 347, fis. 16, FIGS, 15. 16 Synthecium elegans Allman, ($72: 229, Black- hurn, 1942; 111. Synthecium subyentricosum Bale, 19)4az 5, pl. 1, figs. 3-5; 1915: 265, Records; R, 34 m, on Herdmenia memeasy S, 18-25 m, on stem of Therocerpuy eivuri- catus var. eystifera; Stn. F, 65 m,. on worm tubes with Diphasia subcarinate Marerial: Several immature colonies: one fer- tile stem. Stems monosiphonic, flexuons, to 2 cm long; no secondary branching, but a few tendrils given off distal ends of hranches, Proxi- mal stem internodes with 1-3 pairs of opposite hydrothecae; succeeding internodes 1,5-1.8 mm long, a pair of opposite hydrothecae in middie of internode, und u pair of opposite, distally situated hydrocladia. Aydrothecae of variable shape, generally tubular. three quarters of length adnate to intemode, free adcauline wall 0,07-0.15 mm Jong, fixed wall 0.42-0.45 ram: abcauline wall 0.58-0.44 mm long. A delicate internal sheath clearly visible i many hydrothecae, Murgin of hydrutheca sinuous, sligbtly everted, O18-0.19 mm in diam., a few marginal rcduplications. Gero- theca—a single immature individual prowing from the orifice of one of the second pair of hydrothecue on basal stem internode. Calour —white, with trace of purple. Remarks: The single immature gonothecs iden- ties the Pearson J, material with 8, swhvenrri- casum Bale. recognised by Ralph (1958) as a varietal form of §. elegans Allman, 168 JEANETTE BE, WATSON 15 Zygophylax antipathes (Lamarck). Portion of branch showing hydrothecae with everted margins and regenerated hydrothecal pedicels, . Ophiodissa blackburni n.sp. From holotype. Fig, 10—Hydrorhiza and stem with secon- dary hydrophorcs and reduplicated margins. Fig. 11.—Reduplicated hydrophores, en- larged Fig. 12.— Nematothecae, enlarged. Halecium sp, 1. Whole stem, showing growth habit. Halecium sp, 2. Part of stem showing hydraphores and growth habit. » Synthecium elegans forma subventricosum Bale. Fig. 15—Part of stem. Fig. 16—Imma- ture gonotheca. . Synthecium dentigerum Jarvis, Fig. 17W—Part of branch with subupposite to opposite hydrothecae. Fig. 18—Hydrothecae enlarged, showing internal adcauline teeth. HYDROIDS 149 Although there is considerable variation in shape of the hydrothecac among the specimens, most aré tubular and closely adnate to the hydrocladium, not ventricose, as described by Bale for his specimens from the Great Austsa- lian Bight, Morcoyer, there is only one pair of opposite hydrothecae in the middle of each of the distal stem internodes, and a pair of oppo- site. distal hydrocladia, and the hydrothecal marvins are decidedly sinuated. all features considered by Bale to be criteria distinguishing S, parulum Busk. Thus, S. vlegany forma subventricasiuint may eventually prove to be a synonym of 3. pata lum. However, in view of the lack of adequate fertile material, the fact that the typo of &S. patulernt is not known to exist, and the possi- bility that sexual dimorphism may occur, it is hest to keep the species separate at present. Syutheciurt dentigerum Jarvis, 1922: 344, pl, 25. fig. 15. Totton, 1930: 172. Millard, 1944-24. fig. 6, FIGS. 17, 18 Records: S, 23 mon stem of Sertnlaria un- gaiculata and Meramenntig momus Marerials Five infertile stems, to 2 em long. Stas monosiphonic, basal internodes fong.. 3443.6 mm, with 5 pairs of opposite hydro- thecac: each succeeding internode with 2-3 pairs of hydrothecae in mid region, followed by a pair of opposite hydrocladia. Aydrocladix ansing perpendicular to stem from a distinct proximal joint; unustomoses. and some secon- dary branching oceur, Aydrorthecue almost titbular, adnate for two thirds their length, fixed adcauline wall 0.45-0.51 mm long. free wall (.15-1.2 mm: abcauline wall 0,36—-0.42 mm. Murgin narrow. sinuated, with slightly everted cim, 0.21-0.27 mro in diam. Proximal hydrocladial hydrothecae subalternate, hecom- ing opposite distally. {One stem has alternate hydrothecae with the abcauling wall hent sharply outwards.) Adcauline submarginal tooth present in most hydrothecae, variable from wedge-shaped to a mere thickening of the udeauline wall, No ahcauline teeth or marginal teduplications, Remarks: Three specics of Synthecine with internal teeth have been described. §. carinassei Totton, 1930, 8S. singulare Billard, 1935, and 8. dentigeriuim Jarvis, 1922. The Pearson [. speci- mens are larger than 8, carinatum and smaller than 3. wingulere, but fall well within the range giver by Millard (1964) for S. denligernen. The specimens are distinguishable from S$. ev. guns forma sithventricosum Bale, from Pear- son 1, only by the presence of the internal suts- marginal tooth, which is however not developed at all in some hydrothecae, the most prominent tecth being associated with those hydrothecae which have a flexure of the ab- cantine wall, Although the present matertal differs in. some respecis [rom desenptions of §, dentigerym in size of the colonies and arrange- ment of dhe stem hydrothecne, these are neither sulfigicntly constant nor importam characters to Wattant the erection of a new species, This is the first record of S. dentiveruen from Austrahan waters. It has been reported twice previously, from the Indian Ocean pnd South Africa. Fumily SERTULARRDAK Thyroscyphus marginatus (Bale, 1884), Bale, 1915; 245, Stechow. 1925: 217. Black- burn, 1942: 112. Campianularia marginata Pale, 1884; 154, pl. 1, fig, 2; 1888; 758: 1914) SI. Bartlelt, 1907: 42. Records: R, [4-30 m on algac and sponge; 5, 22-30 m on Sergewsum varians Material Four infertile colonies ot u few stems each. Aydrorhiza a simple tube, lagsely wound on substrate. Sven simple, to 1 cm lung, smooth or slightly anoulated, diam. increasing distally, a distinct transverse joint just shove junction with hydrorhiza, Pedicely of hydro- thecac 1.95-2.7 mm long, 0.25 mm in «liam distally. In one stem, 2 branches ate given off side by siule, 1 short, terminating in a hydro- theca, the other continuing normal growth. giv- ing off a pedicel distally. Hydrothecal marain with +4 teeth, 4 valved operculum, and thickened submarginal ring, Depth of hydro- theca, 1.5 mm: diam. at margm, (.73-1-21 min. Remarks: This agrees fairty well with descrip- tions of T. marginatus given by Bale. Parascyphus simplex (Lumouroux, 1816). Blackburn, 1942: 112, Ralph, 1961a; 755, fiz. 1. Stechow, 1925; 224. Laomedea simplex Lamouroux, 1816; 204. Cumpanularia siraples (Lamouroux). Bale, 1884: 58. Pantponaitaris raridentata Hale. 1894" 98, pl, 3, &, 3, Tivrascyphus simplex CLameureux), Hodgson. 1980; 10, fiz, 22. Records; R, 34 m, on sponge and Aere- maria moms on vertical walls; § 25 m, an Thecocarpus divaricarns, Murerial) A few infertile colonies, Sreme short. unbranched, t9 5S mm long. Averothecae 170 swollen on proximal adcauline walls same with a short pedicel, Stem apophyses pronounced, many with a constriction marking the site of growth regeneration after breakage. Remarks: The stem apophyses figured by Hudy- son (1950) and Ralph (1961) appear to merge into the base of the hydrothecae, Bale’s (1894) figure shows a more pronounced apophysis. similar to those of the Pearson TI. specimens. Diphasia subcarinata (Busk, 1852). Bale, 1884: 102, pl. 4, fig, 1. pl. 19, fig. 18; 19144; 7; 1915; 264, Ritchie, 1911; 850. Hodgson, 1950: 20, figs. 34. 35. Ralph. 1961a: 764. fig. 5, Shepherd & Watson, 1970: 140. Serratia sithearinata Busk, 1852 390, Records; R, 20-34 m on bryozoa; 8, 25 m on Amansia pinnatifida and Herdimania mranuiss Str. F635 m, on worn tube. Maretialy Many infertile unbranched colonies 0.5-1 em high. C'oleur—dark brown. Remurks: ‘The keel deseribed by Bale (1884) in his Victorian material is ptesent in the Pear- son [. specimens only as an indistinct ridge passing between the Jateral maryinal tooth and the adewuline thecal wall. Ralph (1961) notes the presence of the ridge as a “prominent fea- ture” un her New Zealend specimens, but Hodgson (1950) was unable to find the ridge in his. Tasmanian material. Stercatheca elongats (Lamouroux, 1816). eae Lene, 23. figs. 38, 39, Ralph, 1961: 762, fig. 4. Shepherd & Watson. 1970; tag bert itaria sian Lamouroux, 7816: 189, pl, Bale, 1884; 75, pl, 6, figs. 7, 8 pl 19, re, 7: 19)3: 277. Mulder & Trebitcock, 19t4a; 3, pl, t, figs, 7-10. Records: R, 30-45 m; S, 12 m, of Srene- claudia australis, Phacelocurpus lahillaradiers, Scvrathalia dorvearpa and Aerovarpia pani- culdta. Materiel: luxuriant colonies, some fertile. Sremy 4-5 cm long, Gonothecae with long horned processes. Remarks: §. clangata is one of the commanest epiphytic hydroids of the southern Australian coastlins. The Pearson f. specimens correspond to the “short stemmed ocean form" of Mulder & Trebileoek (19148). 8. eloneuta shows a wide choice of algal substrate and consideruble tolerance of environmental conditions. The stems of the present specimens Were fice of the encrusting coralline alga usually axsocinted with this species, IFANETTE k, WATSON Crateritheca sacanthostoma (Bale, 1882), Ralph, !96la; 756, fig. 2. Shepherd & Watson, 1970: 140. Millard, 1964; 26, fig, 7. Sermlaria ariel embeeeis rn 1882; 23, pl £2. Fig. 4; R84: 8&5, pl. 4, figs. 7. 8: 1973: 434. Bartlert 1907; 44, hile * Trebileock, 1914) Stereotheed acanthesionta (Bale), Stechew: 1919; 103. Blackburn, 1942. 112. Records; R, 24-33 mm. of sponge and red algae, Material: Two colonies of 4 few stems each. Stenisto 32cm long, Remarks: The Specimens agree exactly with Bale’s description of 3, acanthosrania. Crateritheca crenata (Bale. 1854), 1941a: 757, fig, 2. FIG. 19 Sertalaria crenata Bale, 1884: 86, pl. 4, fig. 2. Record: R, 33 m, on brown algue. Material: Two fragmentary infertile stems. Hydrorhiza tubular, winding. Sten fragments 2.em Jong, with 4-6 deep proximal annulations, followed by a short athecate internode below first branch, Internodes 0.13-0.26 mm_ tong. 0.04-0,06 mm in diam. ai node. Remarks: The Pearson 1. specimens have a much less pronounced outward bend of the dis- tal thecal wall than C. crenara figured by Bale (1884), However, a microslide of C. cremara trom Snapper Point, Vic. in the Bale collection of the NMY, compares very closely with the Pearson [. material. This is the second record of the species, and 4 new record for §, Aust. (Other locality— Port Phillip Bay. Vic.) Salacta obliquanoda Mulder & ‘frebilock, 1914). Ralph, FIG. 20 Sertularia obliqtanoda Mulder & Trebilcock, (9)3b: 41, pl. 5, fig, 1, Stechow, 1924; 106. Shepherd & Watson, 1970; 140), Records: R, 18-46 m, on several species of red algae, including Metunnstophora flabel- leva, bryozoan, und sponge, Meverial; Luxuriont colonies. — Epiphytic colonies fertile, Aydrerhiza loose, tubular. Stems simple, to 8 mm high, some giving olf distal tendrils which form new stolons, Stem Interrodes variuble in length, 0.54-0.46 mm. width at base of hydrotheca, 0.18-0.24 mm. joints oblique, best developed on short inter- nodes, indistinct or absent on long internodes, Hiydrowivese similar to the description given ELYDROIDS Wt by Mulder & Trebilcock, but the hydrothecal aperture is oblique, mot vertical, sloping diagonally back towards the stem in a line: parallel with the abcuufine wall. Length of free adcauline wall 0,12-0.18 mm, fixed adcauline wall, 6.24-0,27 mm, abcauline wall, 0.21-0.30 mm long. Margin with 2 shatp adcauline teeth, and q thickening of thecal wail in the base ot the abcuuline sinus; width of margin 0.06-0.15 mm. Gonothecae large, barrel-shaped, |-53— 1.6 mm Jong, 0.96-1.06 mm wide, with 6-8 deep annulations, a circlet of hooked teeth be- law tim. Usually 1 gonotheca on a stem, borne helow the proximal hydrotheca; male and fe male gonophores on the one colony, Remarns; With the exception of the somewhat longer stem internodes and more oblique aper- ture, the Pearson I, specimens compare closely with the type of Sertu/uria ebliqvaneda in the collection of the NMY. Blackburn (1938, p. 31% 1942. p. 113) listed Dynamena cornicing McGrady, 1858, among the hydroids of the Sir Joseph Banks Group, D. cornicina (=Serrularia complexa Clarke, 1879) (see Bale 1885, p. 769; Billard 1925, p. 1838) and S& obliquanods are very similar, and are difficult to distinguish oxeept in fresh fertile material. However, the hydro- thecae of D. cornivine ave larger, and the aper- tural teeth are more Jalerally situated, The ab- cauline opercular flap, easily visible in the present material. clearly distinguishes 5. obfi- quanode frum D. carnicine. The present apecimens also resemble Triden- tara rurbinata ({Lamouroux, 1816) (Stechow 1925, p. 223) particularly in the presence of the abcauline fiap ond the thickening of the abcauline wall. ‘The status of this group needs further elucidation, S. obliqnanade is one of the commonest species in the collection, This is the first definite record of S, ebliavanada for S. Aust, (Other localities—Torguay and Barwon Heads, Vic, } Sertularella robusta Coughtrey, 1876; 300, fig. 22: Blackburn, 1942; 115. Hodgson, 1950: 33, fig. 53. Ralph, 19la: 824. fig. 22, Shepherd & Watson, 1970: 140. FIG, 71 Records; R, 24-33 m: S, 15-24 m, on Ballia callitricha, Laurencia elata. Herdmania momus, bryozou. and sponge, Marerial> Numerous infertile colonics, Stems simple, iinbranched, te | cm Jong, arising fram a tubular fydrerhiza, Stern internodes variable in length, O.42-1,14 mm, but fairly constant in moimum width, 0O15-0.18 mm. measured just below hydrotheca. Aydrothecae distal on jong internodes, occupying most of the length of short internodes. Length of free adcauline wall 0.3 mo, fixed adcauline wall 0.24 mm; abcauline wall 0.42 mm; maximum width af hydrothees, 0.24 mm. Thecal walls moderately to faintly annulated with 2-3 broad undulations passing around widest purt of hydrotheca. Remarks: Following Ralph (1961a), Lhose stems with a fairly thick perisare aid annulated thecal walls, even though the unnulations may be Faint, are assigned to S. robaester. Sertularella simplex (Hutton, 1873). Ralph, 19fla; $21, fig, 21. FIG. 22 Sevtularia simplex Hution, 1873; 257. Sertulerella peregeina Rule, 1926; 19. fig, 4. Records: R, 30 m, on the stem of Thece- carpus divaricatus var, cystifera, Herdmania momus, and on bryozoa. Material: Colonies of a few Fertile stems, Streams to 1 em long, occasionally branched, arising from a tubular hydrorhiza. Stems smouth, proximal internode athecate, with a few in- definite snnulations, nodes distinct, sloping al- ternately right and left, Internodes fairly tong, 0.39-0.60 mm, becoming progressively shorter distally, until hydrotheca occupies about two- thirds of internode. Width of internode below hydrotheca, 017-020 mm. Branches, when present, arising just below the hydrotheca, the first branch internode with 2-3 annutations. Tendrils present, growing from the distal ends of stems and from broken hydrathecae. Hydro- thecae with 3 internal submuarginal teeth—l #beauline, 2 adcauline; thecal walls thin and smooth, length of free adeauline wall variable, 0.33-0.40 mm, fixed wall, 0.25-0.27 mm; abcauline wall, 0.52-0,54 mm: maximum width of hydrotheca, 0.22-0.27 mm. Margin showing occasional reduplications, Remarks; The material from Pearson I,,, although variable, falls well within the cange of variation of S. simplex defined by Ralph (1961a). The specimens assigned here to S. simplex are easily distinguished from 4, rehbuxia from Peurson 1, by the generally larger and smoother walled hydrothecae- Bule (1926) erected Sertnfarella peregrina to include hydroids from Bass Strait and Port Phillip formerly referred to Sertularella paly- zonias und S. guudichardi. S. peregrina is indis- inguishable from §. simplex as now defined, 72 JEANETTE accordingly S. peregrina is here referred te the synonymy of S. simplex. A new record for §. Ausr. Sertularellu annulaventricosa Mulder & ‘Trebil- cock, 1915: 34, pl, 7, fig 1, pb 8, fig. 4. FIG. 23 Senilareta undulata Bale, 1915: 284, pl, 46, Hig. ). Hodgson, 1950; 34, fig, 59, Records: R, 33 m, on Sarpaysunt sp., on red algae, und bryozoa. Muterials Colonies moderately abundant, infer- tilt, Hydrorhize wubular, Siems simple, to 5mm long, with 2-4 hydrothecae (exceptionally, i stem has 10 hydrotheeae; another is branched) hut. many hydrotheeve arising singly from hydrorhiza, Stems annulated proximally, annu- lafions extending to buse of first hydrotheca, {nternedes 0.30-0,51 mm long, width helow hydrotheca, 0.18 mm. /lydroecaue barrel- shaped, 0,27-0,36 mm in diam, at widest part, Margin 0.15-0.24 mm in diam., depth trom margin to base, 0.30-0.36 mm. Remarks: The holotype microslide of S. annti- laveninicesa in the collection of the NMV has longer stem internodes than the Pearson I. specimens, and is unbranched, although Mulder & Vrebilcock note that “one specimen shows signs of having been slightly branched”. Vhe hydrothecal walls of the type are fairly. smooth. with w ledge passing around the hydrotheca u little below the margin. The walls uf the Pear- sou 1. specimens are not a3 smooth as these af the type, and the submarginal ledge is replaced by I-2 annular ridges. giving the hydrotheca a crumpled appearance. As in the type material, the aperture of the present material is some- what variable in diam., ranging from 4 narrow orifice ta almost the complete width of the hydrotheca- ‘This is the third record of the species, and a new récord fur S. Aust. (Other loculities central Victorian coastline, ancl Tasmania). EF. WAISON Sertulurella ayrilia n.sp. FIGS, 24, 25 Type Maternal and Records: Holotype, NMV GI%64, microslide; paratypes, Gi96S, G1966, G1967, inicroslides; SAM H35, microslide; holotype and paratypes from 8, 13 m, On Sergessunr verruculosum. Dexerigtion from holotype ana puraly pes: Stems simple, short, to 4 mm Jong, unbranched, aris- ing from a thin tubular hydrorhiza. First stem intetnodes short, with 3 proximal annulations: succeeding internades of variable length, 6.32— 0.53 mm, widening from w narrow oblique proximal node, 0.04-0,.08 mm in diam, te base of hydroiheca. Nodes sloping alternately left and right, with I-2 oblique annulations, re- mainder of internode smooth, Mydrothecae dis- tal on internode, alternate, a. maximum of & on stem, each sloping outwards parallel with line of internode, giving stem a zig zaz appear- ance. Body of hydrotheca long, almost. cylin- drical, slightly swollen at junction with inter- node. 016-019 mm in diam. Adcauline wall with 5—7 uniform, rounded annulations, most prominent across widest part of hydrotheca, but reduced to 4-6 on abcauline wall, fading out proximally. Adcauline wall arched out- wards, abcauline wall inflexed into .a long, nar- tuw neck, 0.10-0.20 mm at narrowest dian, expanding again to margin. Length of free ad- cauline wall, 0.36~0.45 mm, fixed adeauline wall. 0.12~0.14 mm; abcauline wall, 0.32-0.37 mm. Aperture facing outwards and slightly down. Margin, 0.11-0.14 mm in dian, with 4 broad, low teeth, the adcauline tooth most prominent; 3 strongly developed internal sub- marginal teeth in theeal neck—2 identical dorso-lateral bract-like teeth, and | long peg- shaped sbcauline tooth. Ayedranth — in- sufficiently preserved for description, but shows evidence of an abecauline caecum. Gonethecu— 1 immituce individual, arising from the base SK SSeS One stem jnternode showing hydrothecac Fig. 19. Craterithecu crenata (Bale). Part of branch with three hydrothecae. Fig- 2d, Salieia ebliqnanoda (Mulder & ‘Trebilgock), with abcuuline opercular flap. Fig. il Serlaretla robusta Coughtrey. Part of stem showing hydrothecae with shallowly anniu- lated walls, and hydranth with abcauline caecum, Fig. 22. Seetularclla sitnplex (Wutton). Part of stem showing smooth-walled hydrothecse: Fig, 24, Sertularella annulaventricosa Mulder & Trebileock, Pact of stem. Figs. 24.25. Sertularella avrilia m3p. From holotype, Fig, 24.—Whole stem. Fig, 25,—Part of stem, enlarged, showing hydrothecac and internal submarginal teeth, Fig, 26, Seriularetia sp. 1, Whole stem with two hydrothecae, Fig. 27. Sermlaretla sp. 2. Part of stem with two hydrothecue, Figs, 28-90. Symplectoyesphus vostratus tsp. Big. 28.- Stem with one hydrotheca and ponotheca, from holotype colony. Fig. 29.—Stem with two hydrothecae: from paratypes, Fig. 30-— Hydrotheca, lateral view, showing internal submarginal teeth, from paratype. HYDROIDS 173 174 of a proximal hydrotheca; body strongly ribbed, with signs of the development of a slender ter- minal neck and 4 blunt spines. Remurks: &, aveilia resembles both 5. roluse (Couhtrey, 1876) and S. gilehristi Millard, 1964. However, 3. aveifia is smaller than S. robusta, the hydrothecae jee more strongly anuulated, and it is further distinguished by the long, curved thecal neck, Although S. evrilia shows some affinitics with S. gilchrisri, this Seuth African species is a larve, branching form, with fascicled stem, and a shorter, Icss conspicuously arched thecal neck, Sertulurella sp, 1, FIG. 26 Revords: R. 21-33 m, on Lawreneia elata, Herdmania momus, Halopteris campanuia var. campattula, and bryozoa. Material; Numerous infertile colonies, Stems simple, monesiphonic, unbranched. straggling. arising from a tubular hydrorhiza 6,05 mm in diam, Stems 10 3 mm long, first stem internode short, with 2-3 indefinite annulations, following internodes thecate, of variable length, O0.06—- 0.24 mm, irregularly annulated except just be- low hydrotheca, Nodes distinct, sloping alter nately right and Jeft, 0.04-0.06 mm in dian, measured just below hydrotheca, Aydrothecae distal on internode, a maximum of 4 on stem: body of tfydrotheca barrel-shaped, one third to one half free of internode: Jength of fixed ad- cavline wall, 0.11-0.14 mm, free adcauline wall, O.15-0,24 mm) abcauline will, 0,25-0,34 mm; maximum width of hydrotheca at junction of udeuuline wall with internode, 0.20 mm, hydrotheca gradually narrowing to margin. ‘Thecal wall with S—7 strong, entire annulations, most marked in mid-region, annulations fading out towards margin, Margin variable in diam., 0,08-0.13 mm, with 4 sharp, equidistant tecth, Nydranth with abcauline caecum, Colaur— yellow-brown. Remarks; The species resembles §. angulosa Bale, 1894 (= S. robuyta Ralph, 1961) but is a smaller species, with much more deeply in- cised thecal ridges. [t is further distinguished from §. rebusta by its straggling growth habit and the large oumber of hydrothecse arising directly from the hydrorhiza. Although displaying » wide choice of sub- sttate, occurring on algae, ascidigns, hryozoa, und other hydroids, this Sertutdrelld was recorded only on the exposed site, where is was very abundant. JIEANKTTE B, WAISON lt seems likely that this is 2 new species, tut is indeterminate until fertile material is found, Sertularetla sp. 2. FIG. 27 Record: R, 18m, no substrate recorded. Marerial; Threc fragmentary infertile stems de- tuched from the hydrorhiza, Stems straight, un- branched, occasionally bent slightly at u node, pensare very thick und brittle, Intemodes of variable length, 0.48-0.96 mm, nodes oblique. sluping alternately lefrand right, angle of slope variable, Internode narrowest at node, 0.18- 0.24 mm in diam., followed by 1-2 proximal annulations, widening to base of hydrotheca; width of internode at base of hydrotheca, 0.27— 0.36 mm. Hydrothecae occupying distal half to two-thirds of internode, sfanding out at about 30)° to axis, very large, variable in shape, either cylindrical, or with a slight distal narrowing be- hind margin, 5 distinct annulations passing completely around hydrotheca, the strongest in the mid-region of the abcauline wall, fading out proximally, annulations Jess distinct on alder hydrothecue, Length of free adcauline wall. 0.39-0.48 mm, fixed adcauline wall 0.36— 0.45 mm; abcauline wall 0.66—-0.72 mm. Mar- gin O.33--0.51 mm in diam.. thickened, with 4+ low, blunt, slightly everted teeth. Operculum of 4 flaps. Hydrenth not well preserved, but an abcauline caccum may be present. Remarks: The hydrothecae are distinctive in shape, and are the largest recorded in Austra- lian Waters for Sertularella. This is almost cer- tainly a new species, but confirmation nist awail the collection of adequate and fertile material. Symplectoscyphos Jongithecus (Bale, 1883). Sertularella longithecu Bule, 1888: 762, pl. 16, fie. 5, 6; 1894: 101, pl 4, figs 7-9. Record: Sta, F, 65 m, no substrate recorded. Murertal: A few straggling infertile branched stems to ¥ cm Jong. Stem internodes straight. 0.54-0.75 mm long, nodes well defined, slop- ing alternately right and Jeft. Branches given off from front of stem opposite base of hydro- thecu. Hydrothecue Jong, tubular, narrowing distally towards margin; length of free adcau- line wall, 0.244036 mm. Margin, 0.15-0.18 om in diam, One hydrotheca shows regenera- tion after breakage at base. Remarks: The Pearson I, material compares well with Bale's (1888) specimens from Port Dennison and Port Phillip Bay. bat they have HY DROLDS a shorter length of hydrotheca free of the inter- node than Ritchie’s (1911) specimens from Wata Mooli, N.S.W. This is only the fourth record of this ipparently rare deeper water species, and a new record for S. Aust, Symplectoscyphus sobdichotomes (Kirchen- pauer, 1884). Ralph, 1961a: 813, fig. 20, Sertnlarelia suhdichatoma Kirchenpauer, 1884: 46, pl. 16, fig, 1. Bale, 1Y¥I4a: 20 (discussion). Records: R, 30 m, on bryozoa; Sto. F. 65 m, on bryozoa, Marevial> Two colonies, each of a few infertile stems. Siemy straggling, to 4 cm long, alter- nately, but irregularly branched. Nodes present on stem and branches, stem internodes indis- tinct, 1-3 annular constrictions at junction of hranch with stem: several branches terminating in tangled anastomoses. Hydroshecae somewhat conical, with & slight concavity in middle of abesuline wall; a fine diagonal line running From the base of the adecauline wall to a small internal pee in the flexure af the abcauline wall, Remarks; The Pearson |, specimens compare closely with microslides of Sertularefla divari- cata from the Great Australian Bight in the collection of the NMV (Bale 1914a. p, 20). Svmplectoscyphus neglectus (Thompson, 1879). Shepherd & Watson, 1970; 140, Sertutlarella neglecta Thompson, 1879: 100, pt, 15, fig. 1. Bale, 1884: 110. pl. 3, fig. 3, pl. 19, fig. 22, 23; 1915: 287. Blackhurn, 1942: 115, Syinnlectoseyohus sp. Ralph, 1966: 163, figs. ~4 Records: R, 25-30 m, on Delivea pulehra, Metaconfolithon charoides, and other red and hrown algae. Material: Luxuriant fertile colonies. Stems to 2 om long, beginning with 2-3 oblique proximal twists, branches suballternate, no secondary branching, but occasionally a branch produced into a tendril. Hydrothecae triangulat in see- finn in young stems, with 3-4 distinet annular ridges, thecal walls of mature specimens much thickened and rounded, the annulations less dis- tinct: marginal teeth of younger hydrothecae long and sharply pointed, blunt in older speci- mens. One-3 smal) internal submuarginal teeth, sometimes not developed, but in mature hydro- theeae may be thickened and projecting into centre of cell, Gonorhecae abundant, male and female on separate stems. Female gonophores borne thickly on stem and proximal part of branches; male gonophores bome only on mid- 175 region and distal part of branches, Both sexes on a short pedicel arising beside a hydrotheca; hady with 10-15 annulations and 2 hollow. conical distal processes. Female gonotheca stout, inflated, widest near middle, blastostyle spindle-shaped, supporting 4 cluster of ova. Male gonotheca long, narrow, widest near base, with a short distal obliquely inclined neck, blistostyle thin, rod-shaped, becoming indis- tinet distally. Remarks: Bale (1884) in his redescription of 8. neglectus, had only dried material before him, and inferred the transversely wrinkled. tiangular hydrothecae to be artifacts of drying. However, much of the present material, par- ticularly the younger stems, shows this to be anormal character of the species. Bale’s surmise that 8, neglects would show sexual dimorphism is demonstrated hy the Pearson I, material. His figure “a” (PI. XTX, fig, 23) with “two latge conical hollow teeth, one more elevated than the other” ts a female gonotheea, and gonotheca “h" (fig. 22) with “teeth smaller and about equally elevated” is male. Tn the Pearson lt. material, the tooth-like conical processes of the female gonothecae are of approximately equal hetght, while those of the male are of unequal length and fairly short, hat this is variable througheut the range of specimens. Ralph (1966) described and figuied Symplectoveyphus sp. (from Port Phillip Heads) with smooth hydrothecac of triangular section and sharply erect marginn) teeth. Although the hydrothecue are smoother than usual, the two latter characters clearly distin- guish her material as young specimens of S. neplectus, 5S. neplectus is a very common epiphytic hydroid in southern Australian waters, occurr- ing on a variety of algae, Ii is easily recusmised in the ficld by the incurved habit of the branches, the encfustation of pink coralline ilgae usually present, and the bright ycllow gonothecav. The short marginal teeth seen on alder hydrothecac are probably the result of constant abrasion against other slems and algae in the very turbulent conditione in which it is usually found. Symplectoscyphus indivisus (Bale, 1882). Raiph, 1961a; 803, fg. 15. Shepherd & Watson, 1970: 140. Sertataretia indivisa Bale, 1882: 24, pl. 12, fig, 7; (8&4 105, pl. 3, fig, 4, pl 19, fig, 27; 1915- 285, Biackburn. 1942: 115. Records; KR, 21-45 m, on Lauretivia elata aml Sargessam spinuligerum: S$, 12-30 m, 176 on Sargessan spp, Déistreniiune sp. and Polvsiphenia sp- Material: Colonics abundant, 1 colony tertile, growing from a loosely wound hydrorhiza. Stems to S mm long; gonothecae clustered thickly at base of stems. Colour—bright yellow. Remarks: The colonies fall within the known range. of variation of S. indivisus, but are separable into 2 distinet morphological groups. The first group comprises stems with short, strongly undulated internodes, often com- pletely occupied by the hydrotheca, The hydro- thecae are inflated, irregularly undulated. with a short submarginal neck, The gonothecae are squat, deeply crumpled, with very short pedi- vel, This group compares with Bale’s (1888) 5, fudivisa trom Portland, Vic. and figs. 5. 6, of §. varigbilis from Port Jackson. N.S.W. The neck region of the Pearson [.. specimens are however, more contracted than those figured by Bale. The stem internodes of the second group are longer. and both internodes and hydrothecie are less inflated. than those of the first group- The thecal wall is only occasionally faintly uo- dulated, and the neck region Is longer, The colonics ure infertile. There ws thus a goal correlation between stem morphology and environmental condi- tions. as the robust fertile) stems were found only on the rough-water site. whereas the mure ficxuous (infertile) stems occurred only on the sheltered side of the island, Symplectoscyphus pygmaeus? (Bale, 1882}. Serrvlarctla premaeus Bale, 882: 25. pl, 12, fig. 4; 1884; LOS, pl. 3, fig. &. pl. 19, fie. 19. Biackilrn. 1942: 115, Hodgson, 1950: 3h, figs. 63, 64, Symplectoveyphus pygmaeus (Bale). Ralph, 1961a: £05, fg. 16. Records: R, 18-30 m, on Herdmania moms, bryozaa and compound ascidians: §, 18-24 m. on stem of Thecocarpus divari- cafes var. eystifera, Marerial: Infertile colonies comprising a few stems to 4 mm long. Coleur-—hright yellow, Remarks: It is difficulr to distinguish between infertile muteriul of S. pygmaens and &, ren- roni (Bartlett. 1907), Ralph (1961) distin- guishes between the two species on the line of fine dots passing from the base of the adeauline wall to a point one third the distance up the abcauline wall in S. pygmaeus, and a lower diagonal in §. renton?, However. examination of a series of microslides of 4. pygrnenty in the collection of the NMY, shows that this is not JEANETTE E. WATSON a reliahle distinction, as the height of the diagonal varies considerably betweem different stems, and even among hydrotheeae on the same stem. Most of the hydrothecae of the Pearson 1. matenal have # ling of dots joining the ab- cquline wall about one quarter the distance up from the hase, a distance vreater than that given by Ralph as diagnostic for S$. pr prices, the junction being marked by a thickened noich on the inside of the wall, As the Pearson I. specimens most closely resemble 5, pyenraens, especially one slide in the Bale ¢ollection (NMV} labelled “Queenscliff, 1881", the speci- mens are provisionally assigned to this species. Symplectascyphus macrothecus (Bale, 1882). Shepherd & Watson, 1970; 140, Sertulerela mavrofhecn Bole, (882); 25. pl 13. fig, 1; 1X84; 107, pl 3, fe 4. pl 19. fig. 24. Bartlett, 1907: 65, fig. Records: R, 24m, on Acrocarpia paniculate, Materials One infertile colony of a few stems. Hydroerkiza «a coarse: undulating tube, Sremi to 4 mim long, robust, atheeate part very short. with a strong distal constriction. Jnternades conspicuously inflated’ behind hydrotheca, nodes sharply twisted. Aydrothecue large, 2-6 on ster, completely occupying internode; fixed adcauline wall 0.18-0.20 mm. free adewuline wall 0.35-0.40 mm; abcauline wall 0.35-0.40 mm. Thecal wall smooth, with a noteh on sh- cuuline side below margin, opposite the sub- marginal tooth. Margin 0.15-0.20 mm in diam, tnieral view, Three internal submarginal teeth, the aheauline tooth best developed. Remarks; The present material agrees well with deseriptions snd figures by Bale of §. macra- theca. Symplectoscyphus rostratus 1.5p. FIGS. 28-35 Type marerial and Records: Holotype, NMV G1981. microslide--R, 27-30 m, on Surgas- rum verruculosin, G2095, preserved miat- eriul, remainder of helatype colony; para- types, NMV GI982—R, 27-30 m. on Sar- gauss verruenlusim: GAYSA—-R, 33 m. on bryozoa; G1984—R, 27-30 m, on Surgayynnt verruculosunr, mictoshdés: SAM H36——S, 46 m.on ted algac; microslide. Descriptions from haletype and pérarypes: iHydrorhiza tubular, loosely adherent to sub- strate, Stems short, to 2 mm long, unbranched, bearing I-3 hydrathecve, perisare thick and brite. Stem internodes twisted, Inflared behind HYDROIDS "iy hydrotheca. proximal internode with 2-3 annu- lations; width of internode at base of hydro- theca O:.17-0.26 mm. Aydrotfycae alternate, occupying most of internode, directed towards front of stem. cach succeeding internode aris- ing behind base of preeeding hydrotheca, directed ovtwards, giving stem a zig-zag appearance, Hydrotheca barrel-shaped, narraw- ing ta margin, with 2-3 shallow annular ridges passing completely around mid-region of thecal wall, Depth of hydrotheea (from hase to mar- gin) 0.42-0,50 mm; 0,27-0.30 mm. in diam. at widest part. Margit contracted, small, rim heavily thickened, with 3 tecth—1 blunt tooth in the ceatral adcauline position, forming a raised beak-shaped crest: 2 blunt. tow lateral tecith, flanking crest. Abcauline side of margin a shallow curve, Margin 0.12-0.16 mm in diam. (lateral view). 1.10-0.13 mmr high (ad- cauline embayment to crest). Aperture facing obliquely outwards, depressed into the distal ridge of the abcauline wall. Four internal sub- Marginal teethe-2 adcauline, long, flanking Taarginal crest, projecting downwards into cell; I. low and ledge-ike (not well seen in an- terior view) just below margin in the centre of the abcantine embayment, and 1, similar in shape, but smaller, deep in the adenuline side of thecal neck. directly opposite the alcauline submatginal tooth, seen only in lateral view, Hydraeth with abeauline caecum, connected by u delicate web to the abcauline wall belaw the internal tooth. Gonothecae large, ovate, 0.8 mm long, 0.6 mm wide. arising from a short pedicel hetow proximal hydrotheca, with 5 strong, crumpled annular ridges, and 3 low, fairly sharp apertural teeth, Remarks: The material of S. rastrams from Pearson I. included only 2 gontthecae, one of which was immature. S, rostratus is in some Tespects transitional between the smaller forms of 5. indivisns Bale, and S$. snacresiecis Bale, resembling the former in géneral aspect af |he trophosome and gono- some, and the latter in the arrancement oF the imMerrial submarginal teeth, There ts hawever, only | abcauline submarginal tooth in S, ree fratus, compared to 3 in J, macrotherus. fn ¥. indivisns, the 3 mareinal teeth are alternate With the tnaruinal teeth, The raised adcautine crest further distinguishes §. resiralys. Symplectuscyphus epiznicus n.sp. FIGS. 31-33 Type Material and Records; Holotype, NMY G1985, microsiide—S. 20 m, on Theco- rarpus divaricanns van cvatifera; G2096, pre- served material, remainder of holotype co- lony; paratypes, G1986, GI9R7T, GLOSs, microstides—R, 30 m, on TL divaricarer var. evstifera; SAM H33, micrastide, Description fram heletype and peratypest Hydrorhkiza tubular, of same diam. as sterns. Stems simple, short, unbranched, to 7 mm long. Proximal stem mternnde short, athecate. with 4-5 annulations, width 0.13 mm; following internodes of variable Jength. 0.50-1.05 iim, ftydrorhecaé large, pecisarc delicate, alternate. in one plane, a maximum of 4 on stem. nat immersed in internude, distal on long inter- codes, occupying almost the whole Jength of short internodes, without definite floor. barrel- shaped, widest about middle, narrowing only slightly to margin. Leneth of fixed adcauline wall 0.22-0.28 mm, free adcauline wall 0,21- 0,30 mm, ubcauline wall 0.45-0.53 mm. Mar- gin O,28-0.31 mm in diam., thickened, with 3 equi-distant bluntly pointed tecth—1 edceuline, 2 lateral abeauline. Operculum of 3 delicate flaps, No internal submarginal teeth. Hydranth with approx. 24 tentucles, and an abcauline cuecum, Gonetiecae large, ovale, neatly 3 times length of hydrotheca, 1.11-1.35 mm long, widest at top. 0.87-1.02 mm, tapering to a short pedicel arising below proximal hydro- theca, walls fuintly undulated proximally. the anmulations more distinet about mid-region. Aperture small, circular, 0.13-0.15 mm in tlam., depressed into the most distal annula- tion of the gonéthecal wall; 4 very low rounded teeth, Gonophores femule, mature, now filling Pponothecal cavity, with 10-16 eggs, Colanim— yellow. Remarks; The colonies arise from a single sta- fon running up the main stem and branches of the host, the stems and occasional single hydro- thecae given off at irregular intervals. S. eplzeicus resembles one of the farger forms of §,. indivisns (Bale) (ie. “Sernularella feriahiliy’ Bale, 1838) in size and structure, and could easily be confused with this species in preserved material, However, S. epizotcus lacks the internal submarginal teeth which dis- tinguishes 5. indivisns. Sertularia meacrocarpa Bale, 1884: &0, pl. 5, fig. 2, pl. 19, fig. 11: 19l4a! 14; I19[5: 277, Mulder & Trebileock, 1914b; 42, Hodgson, 1950; 27, fig. 47. Shepherd & Watson, 1971: 140, Records: R, 25-34 wy S, 4-25, anvone hol- fasts of red algae. 178 TRANETTR F, WATSON Material: Colonies abundant, growing in thick tangled clusters. Stems us 12 cm long, infertile except for | gonotheca. Colerr—dark hrawn. Remarks: This distinctive species is easily recognized by its dark colour, and large. tangled! colonies which usually grow at the base of ulgue in semi-sheltered situations. Serfularia unguiculata Busk, 1852: 394. Bale, L884: 76, pl. 6, figs. 9-12; L894: 100; L9]4a: 16; 1915: 273. Blackburn, 1942: 113. Hodgson, 1950: 26, figs. 45. 46. Ralph, 1961la: 788, fig. 13, Records: 8, 25 m, on Herdmanta momus, and among algal holdfasts. Material; Several large infertile colonies. Stems short. to 3.5 cm, unbranched, Proximal branch internodes with 3 pairs of hydrotheeae, euch succeeding internode with 2 pairs of hydrothe- cae, nodes. indistinct. Ayedrothecae on branches adnate for two-thirds of length; cauline hydro- thecac not immersed in stem. Colour—orange brown, Remarks; Although shorter, the stems m the present collection conform to Bale’s (1884) description of the thick stemmed, long Inter- node form of $, uaguienlate. Although relatively common at Pearson L, 9. wunrguiculata was restricted to sheltered water. Sertnlaria bicuspidata Lamarck, 1816: 21. Blackburn, 1937: 367. Serthlaria bicornis Bale, 1882: 22, pl. 2, fig. 3) 1884: 83, pl. 5, fig. 9. Records; RB, 45 m, on Rhodopeltis australis und Metamastophora flabellata, Material; A few infertile stems. Stems sttilty erect, branched, to 1 cm long, Colour—dark brown, Remarks: The distinctive paired finger-like pro- cesses flanking the margin distinguish this spe- cies From all other species of Sertularia in Aus- tralian waters, This is the first undoubted record of §. his cuspidara from S. Aust, (Other localities— Queenscliff, and Lady Julia Perey 1., Vic.) Sertularia maccallumi Bartlett, 1907: 62, fg, Mulder & Trebileock. 19144: 7, pl. 1, figs, 3. Bale, 1919; 340. pl. 16. figs. 3, 4, Shepherd & Watson, 1970: 143, Records: R, 25-45 m, on Carpopeltic pfiyl- lopora and Prerocladia licédet. Muterlaly Luxuriam fertile colonies thickly oyer-running algae. Stems to 4 mm long. Sertularia acuta (Stechow, Colowr—hydrorhiza brown, hydrocaulus bright yellow, Remarks: §. maccallumi 15 one of the com- monest. hydroids in the Pearson J. collection. Although both species of algae were also recorded at West L. (Shepherd & Watson 1970), S. wraccallumi was never Found on P, lucida, and only occasionally on C. phyllophera at that locality, 1921), Millard, 1958; 192, fig. 8, Shepherd & Watson, 1970; 140. Sertularia loculosa Bale, 1884: 9), pl, 4. figs. 5,6; (913: 121, pl. 12, figs. 7, 8; M15: 272. Tridentata acuta Stechow, 1921; 231. Sertularia balet Briggs, 1922: 150, Records; R, 45 my, 8.15 m, on Srenecledia australis. Marerial; Abundant fertile colonies, Stems un- branched, fo 5 mm long, internodes with an oblique proximal, and a transverse distal joint; exceplionally, a transverse joint is followed by 2 oblique jomts, Celeyr—yellow. Gonorhecae with 4-5 deep annulations, Reinarks: The Pearson 1, specimens correspond closcly to the short-celled form of “S, loculosa" Bale. Millard (1958, p, 198) distinguishes S, acuta from S, turbinata (Lamouroux, 1816) in her South African material partly by the presence of transverse stem nodes in the former species, and oblique nodes in §. rurpinara. The Pearson T, material has both transverse and oblique joints on the one stem, thus further reducing the difference between these two closely related species. 8. acuta is a common epiphytic species in the collection and is associated with only one specics of alga. Amphisbetia maplestonei (Bale, 1884), Rees & Thursficld, 1965; 142. Shepherd & Wat- son, 1970: 140. Sertularia maplestone’ Bale, fie 4, pL 19, fig. 2 Serfularia bidens Bale, |884:70, pL 6. fiz. 19, fiz. 1; 1914a: 14, Records: R. 34 m; 8, 25 m, among holdfasts. Material: Luxuriant fertile colonies. flexuous, 5-12 em tong. L884: 70, ph 6, 6, pl. algal Stems Remarks: The distal conical processes of the gonothecae are modetately well developed, bul many gonothecae have only 1 process on the abcauline side. TY DROIDS (74 Amphishetia pulchella (Thoinpson, 1879). Shepherd & Watson, 1970: 140. Serndana palehelia Thompson, 1879: 109, pl TX, fies, 3, 3a, Bale, 1884: 71, pl. 6, fig. S, pl 19. tig. 10. Sertularia 1942; 113, Records; R, 45 m, on Praracladia lucida; §, 14 m, on bryozou epiphytic on algac. Marerial: A few infertile stems to | cm long, Remarks: Blackburn (1942) included A. pui- ehella in the synonymy of A, maplestone? al- though A. pulchella is a prior numeé. Although similar in microscopic details of the tropho- seme, the lwo species seem to be distinct, und are readily distinguished by the gonothecue and size of the stem. The stems of A. nwplestere’ ure long and robust, while those of A. pulehella rarely exceed 2 cm. Both species are epiphytic; the larger species, A. smaplesronei, is confined to the hasal parts of algae, while the more deli- cute A. pulehella epiphytises the fronds. Pos- sibly, further work may prove the two tu be ecomarphs of the one apecies. maplesioned (Bale), Blackburn, Amphisbetia olseni nsp. FIGS. 34-37 Type Material and Records; Holotype, NMV G2001, microslide—R, 33 m, on sponge; G2097, preserved material, remainder of holotype colony; paratypes, G2002, G2003, 32004, microslides—R, 33 m. on Herd- munta moms: G2O0S—S, 17-33 m, on brown algae, microslide: G2098, temainder of paratype colony G2003, G2006-—R, 33 m, on red algae, microslide: SAM H34-—R, 33 my, on Sponge. microslide. Description fram holotype and paratypes: Hydrorhiza tubular, Stems to 7 mm long, monosiphonic, stiffly erect, branched. Proximal stem internodes athecate, terminating in a strong V-shaped joint. suceecding internodes thecate, nodes indistinct, but if present. V- shaped, slender. Internodes 0.52 mm Jong, diam. at node, 0,06-0,09 mm; 3 hydrothecie on stem internodes, 1 axillar. 2 subopposite, Branching regularly alternate, up to S branches on stem, atising from a long proximal apo- physis given off at 70° to stem. First branch internode very short, athecate, with a transverse proximal, and V-shaped distal joint; remainder of branch without internodes, but with wp to 5 pairs of hydrothecae. Hydrothecae on hranches subopposite. in 1 plane, adnate approx. two-thirds of their lenzth, saccate, widest near middle. narrowing 2 margin, Fixed adeauline wall 0.12-0.16 mm long, free nd- cauline wall 0.05-0.08 mm, standiag our hori. vontully, of at a slight upward angle from the internode, Abcauline wall 0,16-0,19 mm, a pronounced inflextire about one-third the dis- tance up from the base, followed by 4 sharp outward bend, but this may be reduced te a mere concavity in the abcauline wall, Paired hydrothecae on younger parts of stem and branches in contact along fixed adcauline wall, but separated in older parts of stem) if in con- tuner, the adcauline wall is straight, otherwise it is bent parallel to the inilexure of the ab- eauline wall. Margin with 2 long sharply pointed lateral teeth 0.07 mm long, separated by a deep, almost horizontal abcauline sinus; adcauline wall indented behind matgin. Oper- culum of 2 flaps, abcaulinc component fixed. Aydranth with approx. 12 tentacles, Gono- thecae arising from lower stem behind proximal pair of hydrothecae, large. ovate, fattened, 1,02-1,32 mm tong. Perisare thick, walls smooth, widening distally to a shoulder 0,84- 1.02 mm width, produced inte a pair of short, almost laterally directed spines. Aperture citcu- lu’, 0.35 mm. in diam., with a slightly raised collar and a ring of minute internal denticles. Operculum a. circular flap. Gonothecae empty. Colour—light straw colour, Remarks; The branching in 4. olseni is regu larly alternate, where a branch fails to develop, the stem internode is longer, and has I axillar, and 2 pairs uf subopposite hydrothecac, then branching resumes again, The branches are very brittle and break off eusily wt the slender proximal joint. A. olseni 1s closely reluted to both A. prl- chella (Thompson) and 4, tidens (Bale) in structure of the trophosume and gonosome, but is distinguished from these species by the straighter, Jess flexuous stem, the pronounced concavity of the abcauline thecal wall, the less prominent marginal teeth, the greater propor- tion of the hydrothees adnate to the internode. and the shape of the gonotheca, With one exception (8, 17-33 m), the colo- nies were all found within the same area on the rough water site. A_ olseni is named after Mr. A, M, Olsen, whose interest and encouragement has done much to foster marine science in South Aus- tralia. Amphisbetia minima (Thompson, 1879), Ralph, !96far 774, fig. & Shepherd & Wilson, 1970; 140. FIGS. 37, 38 180 JEANETTE E. WATSON Figs. Figs, Fig. Fig. Fig, Fig. wu SO wus" 38 39 40 4| 31-33. Symplectoscyphus epizoicus n.sp. Fig. 31—Whole stem with gonotheca. Fig. 32 Hy- drotheca enlarged, anterior view, with hydranth. Fig. 33.——-Hydrotheca, lateral view. Drawn from holotype, 34-37. Amphisbetia olseni n.sp. Fig. 34.—Whole stem, from holotype. Fig. 35, part of stem and 38. 39, 40, 41, branch, enlarged. Fig. 36,—Part of stem and gonotheca, from paratype. Fig. 37.— Hydrotheca, enlarged, Amphisbetia minima var. pumiloides Bale. Part of stem with two internodes. Amphisbetia minima var. intermedia Bale. Part of stem with two internodes, Figs. 38 and 39 drawn at same scale for comparison. Amphishelia minuscula Bale. “Short internode form". Amphisbetia minuscula Bale. “Long internode” form. HYDROIDS tat Sertularia minima Thampson, 1879: 104, pl 17, fig, 3, Bale, 1882; 21, 45, pl. 12, fig. 25 1884: $9, pl. 4, figs. 9. 10, pl. 19, figs. 12, 13; 1945; 269; 1924: 248. Mulder & Trefileack, 1914b: 39, Sreehow, 1925. 231, fp. K. Blackburn, 1942: L14. Hadgson, 1950: 23, figs. 41, 42, Millard, 1957; 221. Records; KR, 12-50 m;S, 15-25 m, on algae {see Remarks), Material) Luxunynt fertile colonies, Stents to 35 mm long. Colow7e—tight brown. Remarks; Bale recognized 3 varieties of A- wine jn southern Australian walters, the largest, var, pumtloides Bale, 1884 (from Queenscliff, Vic.), a “typical” farm Irom Port Phillip Bay and New Zealand waters, aud var. iermtedia Bale, 1915, from the Nuyts Acchi- pelago in the Great Australian Bicht. Ralph's (1951) figures und description show her New Zealand specimens. to be closely allied to the Australian typical form, but there are nemato- thecac scattered throughout the hydrocautus, a condition not normally encountered in the Aus- Uulian material. 4 minime is one ol the most abundant hydroids in the Pearson I. collection, und the material exammed falls with little inter- vradation into 2 of the varieties, var. pudai- loides und var. intermedia, Although difficult to distinguish in preserved material, the vyarie- hes are casily separated in mounted prepara- tions. These varieties have not previodsly been recorded together in the one Jocality. The present material corresponding to var. puniufoides is a robust form, conforming to Bale’s (1884) ceseription. The bydrothecye ure almost entircly adnate, and the typical wedge af perisurc belween hydrotheca and internade is well developed. The gonothecue are variable in shape, round Lo clongute mm Jatetal view; those with # raised apertural collar do not have wring of internal submarginal denticles. The var. intermedia, not figured hy Bale. as much smaller, with shorter internodes, and rectilinear hydrethecae. Nematothecae, varying from short cylindrical tubules to mere breaks in the perisarc. are present on all stems, but are cnn- fned to the infrathecal chamber of the proxi- faal hydrothecae. Gonothecae sure round [0 ovate, Dimensions of the 2 varieties from Pearson !. are given for comparison. var. var. _ Dimensians. mat pamileides __fatermecia Internode length 1.35-0,38 A.25-0,37 Digan. al node 0.05-€.08 0.03-0,04 Livdralhecu Tength 24-029 .t7-1.22 With few exceptions (Rilchie I91T), A. mninwe is recorded as an epiphytic species, and at Pearson [, the 2 varieties show a stroug selectivily towards certain species of algae. The var. puumiloides was found only on the robust brown aleae Sargassum bracteolosum, 8, varias, and SY. verrucu/osum, as well as Aero- carpla puniculeta; var. intermedia Was asso- ciated with the more delicate red algae Rhoddy- tnenia australis, Metamasiophera flabellata, Laurencia elata, and Carpopeltiy phytlophora, with one record on the delicate brown alga, Distromium flabellatum. Shepherd & Watson (1970) noted that many commonly epiphytic hydroids show varying degrees olf preference for particular species of algal substrate, but a differential selectivity by varielies of the same species has not previously been recognized. Almost all the colonies have the pegged hydrorhiza typical of A. minima. Bale (1915) and Mulder & Trebileock (19I4u) noted this tact; Ritchie (1931) suggested it muy be a response 10 Wave action, but Ralph (1961) could find “no constant relationship vo enyiron- mental conditions” to accvunt for the thicken- ings, In many of the colonies of both varieties of 4. ntinima from Pearson L, the hydrovhtes is often tubular and loosely winding when in comuct with the curved and cylindrical sur- faces of the lower stems of the ulga, then flat- tening out and developing the transverse murk- ings as the stolon passes onto (he broader fronds. This change in cross section of the stolon may {herefore be etther a response to the greater movement of the algal frond in turbu- lent walter, or it may be related to the narure of the algal surface. The systematic status of the 3 so-called varie- ties of A. minima, and of the whole “A. minha? group, including 4. avniscala Bale, A. fureaie Trask, and A. stuellevi? Bale, needs further clucidation. Tt is possible that all may be ecologic variants of the one species, or several distinct. bur closely reluted species. Amphisbetia minuscula (Bale, 1919), FIGS, 40, 41 Sertifarla minima var. tebathere Mulder & Trebileuck, 1934b: 40, pl. 4. fig 1- sSeesatarte puisifla Bale, 1915: 271, pl. 46, figs. i= Sertifaria minuscila Bale, burn, 1942; 114, Records: R, 30-40 m, on Lauvrencia elite, Disttomiun flabellaiuin, aod Herdmeania moms: S, 25-31) m.ion the stem of Cauuvlerpa sp.. and Halicernaria longirostriy. Morera; Abiadant colonies, some fertile, Stemy simple, to 5 min) long, internodes vari- able. The slems ace divisible into 2 groups—ag 1919; 340, Bliack- 182 long internode group, internodes 1),42—0.44 mm long, anu « short internode group, internodes 0.30-0,.34 mm long. Nodes of both stem groups 0.06 nim wide, indistinct, transverse, occa- sionally a V-shaped joint in distal region of stem. Hvedrethecae similar to deseriptiens al authors, fixed adcauline wall 0.19-0,22 mm, free adcauline wall G.07-0,11 mm; abcauline wall 0.19-().26 mm; an indistinct downwardly curved ridge passing back from the embayment between the marginal teeth into the junction of the adcauline wall with the internode. Gono- thecae 1.20-1.26 mm long, excluding pedicel, maximum width, 0.75-0.97 mm, present only on the “short internode” form. Remarks; The hydrothecae of the “long inter- node” form of the Pearson I. material are larger than those of the “shart mternode” form, but both ate smaller thun measurements from microslides of 4. miinuscula, and the type of “4 minima var. tubathece” in the collection of the NMY. The “long internode” form conforms with measurements ot A. pusilla (Bale), while the “short internode” form is similar to the var. tubatheca of Mulder & Trebilcock. ‘The nemitothecue noted by Bale and Mulder & Trebileock are present in only a few of the proximal sium internodes of the Pearson I. specimens; the intrathecal ridge, noted it the present material, is not present in the type. A. nunascula displays a wide choice of substrate, Some correlation evidently exisis between stem type and environmental conditions, since the “long. internode” form was abundant on the sheltered site, whereas the more robust “short internode” form was found only on the rough- water side of the island. This suggests that deve- lopment of a thickened stem with short intet- nodes is advantageous to withstand rough water conditions. : Family PLUMULARILDAE Pycnotheca producta (Bale, 1882), Plumularia praducta Bale, |882; 34%, pl. TS, fig. 3; 1884: 133, pl, (0, fig. 4; 1894; FTI. Kirehenpuueria prodicta Bale, 1914a; 59, 1915; 302. Blackburn, 1942: 107. Records: R, 24 m. on Distromitin flubetla- wm; 8, 24 m, on Avmenera?, Material A few scuttered infertile colunies. Stemy to F mim lovg. Remarks: The material contorms exactly tu Bale’s description of P. prodnete. Antennecila tubulosa (Bale, | 894), FIG. 42 Piganiasia tihalesa Bale, hes. 2-5, 1894: 114, pl 5, JEANETTE FE. WATSON Records: R, 27-30 m, on bryozoa: S, 26-30) m, On Sargassum sp. Material: Seyeral colonics, cach comprising a tew infertile stems, Stems to 3 mm lone, ansing from a thick hydrorhiza. First internode with a proximal constriction, fllowed by an athe- cate Internode with 1-2 nematothecac and an oblique distal node. Athecate internodes 0,1 1— 0.16 mm long; thecate internodes as described by Bale, 0.27-0.37 mm Jony, with 1 median nematotheca and 2 scoop-shaped lateral nenia- tothecae, Aydrothecae long, 5-G on a stem, proximal part tubular, perisarc thick, adcauline wall 0.25-0.27 mm long; abcauline wall 6,22— 0.30 mm long. distal part of adcauline wall more convex than abcauline side, Margin 0,13- 0.15 mm in diam., deeply sinuated, curving up to meet produced adcauline wall. Co/our— yellow. Remarks: The Pearson L maternal, althougl definitely reterable to 4, rubrilose, nevertheless shows considerable variabilicy in thickness of perisarc, length, diam, af inlernove, and shape of hydrothecae. Bale (1894) comsidered that ef, tebdlosa may be a variant of A. canipannla, or jhe “Antennella” form of an unknown Plu- mularian, As the present matenal shows no sitn of branching, 4. tubulosa may therefore be con- ssdered 4 distinct spectes. This is the second record of 4. rebudosa, anc a first record for S, Aust. (Other locality—Pon Phillip Bay, Vic.) Antennella campanuliformis (Mulder & Trebit- cock, 1909), FIGS. 43, 44 Pienvlocia campanatiformly Mulder & Trebil- cock, 1909F FL, pl. T, figs. 6, 9, 10; T9LT: 115. Records; R. 30-45 m, on Sargassien sp. Lenvrencta elate and Preroelacie lucida. Material: Colonies common, fertile, The spéci- mens contorm to the type microslide of Pfi- mularia campanuliformis in the collection of the NMY. The following description supple- ments that of Mulder & Trebileock, Hyvdrorhiza tabular. Stems to. 1 cm long, first stem internode 0.5 mm long, athevale, with 1-2 hematothecae and 1-2 proximal annulations, distal node oblique, following internodes qlter- nately thecate and athecate. Thecate internodes 0.39-0.45 m Jong, almost entirely oceupied by the hydrotheca, with an oblique proximal node, and a transverse distal node, 0.06-0.09 mm wide. often indistinct; athecate internode short, O.2R8-0.31 mm (measured along base of hydra- HYDROIDS 183 cladium). Hydrarhecae cup-shaped, deep, base curved, abcauline wall 0.20-0.22 mm tong, concave: adcauline wall 0.21-41.25 mm long, straight or wath » slight convexity below the margin, both walls thickened, the abcauline flange eXtending back tu the median nemato- theca, Margin circular, 0.21-0.23 mm in diam., slightly »sinuated, Nemetorhecae large, bithala- mic, O.08-0.L0 mm Jong, distal cup 0.05 mm in diam, 3 on the athecate internode—] median, base stout, cup excavated on adcauline side. 2 laterals below bydrotheca on a very shart apophysis of the hydrocladium, cups nur- row. txcuvated on inner side, sides slightly in- rolled; | on athecate internode, similar ta other's; 2 similar in shape. but larger than cuuline nematothecae on the pedicel of Female gonotheca, facing outwards, cups excavated on the side facing gonotheca; 1 nematotheca on male gonotheca above pedicel. Gonothetae of both sexes on the one stem, arising beside the median nematotheca on theeute internodes. male small, 0.22-0.27 mm long, ovate. 0,10- 0.14 mm wide, only on proximal stem inter- nodes; female large, 0,64-0,66 mm in diam. globular, only on distal internodes; female gonophore of | large egg surrounded by a top- shaped blastostyle. Remarks: Although Mulder & Trehileock des- eribe and figure the hydrotheca of 4. campo- nutiformis as campanulate, this is somewhat misleading, as the type specimens as well as the Pearson [, material have almost tubular hydro- thecae. This is the second record of A. canrpmiuli- fermis, and a first record for S. Aust. (Other locality—Vic_} Antennella secundaria (Gmelin) s. sp. dubia- formis (Mulder & Trehbiloock, 1910), FIGS. 45, 46 Plumelaria debiaformis Mulder & Trebiloock, 1910: 119, pl. 2. fig, 7. Anrennelfa secuytidarin (Gnielin). Billard, 1913: 8. Plamularia stcundarja (Gmelin), Blackburn, 938; 346), Sehizetriche secundaria (Gmelin), Blackburn, 1942: 108. Records: §, 17-27 m, on compound ascidian. Rhodymenia austrulis, Distramiam flabella- tam, Sertuluria unguiculara and sponge. Material; Abundant fertile colonies. Mydrarhiza tubular. Sterns lo 6 mm Tong, perisare delicate. First stem internode Jong, athecate, with 3 nematothecae and oblique distal joint. inter nade oceasionally with | branch, Following internodes allernately theeate amd wthecate, athecate internodes 0.3 mm Tong, with an in- distinct transverse and a strong oblique distal joint: thecate internodes shghtly longer, 0.30— 0.35 mm long. Hydrothecae campanulate, 0,20.-0.22 mm deep, set an un angle of 45° to hydrecladial axis, base flat, abcauline wall slightly thickened, udeyuline wall almost entirely adnate, free part closcly adpressed to internode. Avarefm entire, delicate, 0,26-(,30 mim in diam. Nematothecae as described for 4. secundaria, 2 present on uthecate internode. One small suprathecal nematotheca usually, but not always present in the sinus above the hydro- theca. Genothecae—male and female on the same stem, arising beside the median subhydro- thecal nematotheca, tapering (o a short pedicel. Female globular, flattened, 0.52-0 58 mm long, widest. near niiddle. 0.40-0.44 mm maximum width. cloycd by a thin operculum: 3 nemato- thecne similar to laterals, in hasal region. Male gonotheea small, 0.15-0.20 mm long, 0.12- 0.13 mm wide, with 1 proximal nematotheca, Remarks: The present specimens are identical with 2 microslides of [tagmentary infertile ma- teal of Plamularia dubiaformis Mulder & Trebilcock if whe collection of the NMV. Mulder & Trebilcock. because of poor material, were unuble to establish the presence or ab- sence of the supratheeal nematothecae in P. dudiaformiy. These nematothecac are clearly visible in the Pearson [. material- T have also compared the present material with fertile material of A. secundaria trom Mossel Bay; South Africa. provided by Dr N. A. H. Millard, and with (he exception of the 2 median nematothecac on the athecate inter. node in the Pearson |, specimens (f in the South African material). the twa are indistin- guishuble. As the number of nematothecae on the athccate internode is not a reliable specific clitetion, 1 agree with Billard (1913) and Blackbur (1938) who suggested PL diubia- fermiy would prove to be a synonym of A. secundaria. As the Known South Australian material of A, secundaria always has 2 nematothecas on the athecate internode, compared to 1 in the typical form, und has now been recorded From two widely separated localities (Pcarson I and Vic), it Is here recognived as a subspecies of A. secundaria, Halopteris suteata (Lamarck, 1816) Plurnularia saleata Lamarck, (818: 128. Briggs, 1915: 306, pl, 11, fig, 1. Bale. 1914b> 172. pl. 35, figs. 6, 7; 1915: 296. Plumuteria agliaphenoldes Baie, 1884: 126, pl, 10, fiz. 6. 1x4 JEANETTE Reeordy; Ro 30m, on sandy floor of cavern. Material: Several large Fertile colonies. Sten fuscicled, branched, co 20 em high, growing from a small fibrous rootstock. Colour-—dtatk brown. Reimarks: This species is cusily recognizable thy its large, erect woody stem, colour, and brittle texture. At Pearson 1., A. syleata was found only on the floors of caverns shellored from gtirse: tL hus however also been noted in open water to the east, in Tnvestigator Strait (J.W., unpublished) at depths of 40 m, Hulopteris campanula var. campanula (Busk, 1852). Ralph, 1961 6;47, Plurnelaria carmponita Busk, 1852; 401. Bale, (884: 124. pl. 10. fig. 5: ISEB: 776; 19t3: 134; (475; 245, Hodgson, 1950: 40. fiz. 49. Schizoricha canmpannla (Busk), Blackburn, 1942: 107, Reeords: KR, 35 m, epilithic, Murerial; One infertile calony growing from a common rootstock, Stems —polysiphonic, branched, to 4,5 ¢m high; some secondary branching. C'olouwr—yellow. Renunrks: The specimens agree with descrip- lions of # canzpanule, and A. campanula vat. contpunita oF Ralph (1961b).. Halopteris buski (Bale, (884), Plamularia bushi Bale, 18845 125, pl. (0, fia. 3. pl. U4. figs, 34. 35; 19)4dur 28, 1915: 296. Arives, 1915: 304. Hodgson, 1950: 45, fix. 75. Sehizetricha buski (Bale), Blackburn, 942: 107, Recardy' RR, 30-338m, on Herdinania monies, bryozoa and sponge: Stn. F. 65 m. on werm tube, Mareriul: Scattered voloniex, euch of iu few stems ta 2 em long. One stem with immature inale gonophores Remarks: The Pearson 1 specimens do not aliffer significantly from descriptions of [Bile and Briggs. With one exception (Sin. F) the colonies are all from the exposed side of ihe island. They are short and robust. with deeply incised stem joints; frequently an extra oblique septal Internodal ridge is developed just below the adcauline hydrothecal wall, The stems from less turbulent deeper water (Stn. F) are more fiexuous, wilh indistinct cauline nodes, and alsu lack the oblique hydrocladial septa present in the shallower water specimens. The deeper water stems were scarlet in colour, Whereas the shallower water specimens varied from orange to yellow, E. WATSON Halopteris vupposita (Mulder & Trebileock, 1911). FIG. 47 Plimtlatia appesita Milder & Trebilenck- 1911; 120, pl 2, fig. 5, Thevoedilus oppositus (M. & T,). Blackbilin, 1938s 316, fig, 2) M42; 17. Recardy: S, 30 m, on Sargassum spinuli- gerne and 8. verruculostini. Mererial: Scattered infertile stems to 12 mm long, The specimens compare with the type microslide of Mf. eppeyifa in the collection of the NMV, and allow a fuller description to sup- plement the previous brief description of Mulder & Trebilcock, Stemy with 2-3 indistinct proximal annula- tions, followed by a long athecate internode with 2-3 nematothecae, then alternate thecate and vathecate internodes of approx, the sarne length, 0.27-0.39 mm, athecate internades with a proximal transverse joint and strongly oblique distal hinge-joint, and 2-3 nematothecuc, if 2, they ate ane shove the other: the third, if present, is beside the distal nemalotheci. Hydrocladia opposite. arising behind the cauline hydrothecac in middie of the anter- node, hydrocladia beginning with 2 short athe- cate internodes, the firs. internode the shorter, 0.95=0,.07 mm long, the second 0.07-0.98 mm long, with a transverse proximal, and an oblique distal joint, and occasionally, | nema- totheca. Thecate hydrocladial internades sinii- lar ta stem internode. Hydrothecae campinu- late. 2-3 on hydrocladium, 0.15-0.18 mm deep, set at 45° to hydrocladial axis. Murgin 0.19-0,21 mm diam., slightly sinuated, rim eVveried, with a peak on the abcauline side. Ab- gauline wall 0,12-0,15 mm long, In some hydrothecue a sinall transverse fold near hase. Nematothecae 0,05-0,07 mm long, 2 supra- thecal un stem internodes, 4 on thecate hydro- eladial internodes—1l median, stour at base. distal cup cut away on adcauline side, closels adpressed to internode; 2 lateral stiprathecal. with slender pedicels, an an apaphysis af tke internode, extending above hydrotheca, and 1? small nemalotheca between laterals at hase of hydrotheea. Hydranth with 10-16 tentacles, connected to internode by a small orifice in the upeurve of the abeauline wall, Remarky: The stem of the type is thick and robust, and the athecate siem intemodes ave cunsiderably shorter than the thecate inter- nodes, with deeply constricted nades- The Pearson T, specimens have slender stems, and internodes of neurly equal length, Black- 42, 47. . 48-52. HYDROIDS 0.25mm WU O 5] O-lmm Antennella tubulosa (Bale). Part of stem. » 43,44. Antennella campanuliformis (Mulder & Trebilcock). Fig. 43.—Part of stem with male s. 45, 46, gonophores, Fig. 44——Female gonophore- Antennella secundaria s.sp. dubiaformis (Mulder & Trebilcock). Fig. 45.—Part of stem with two hydrothecae, Fig. 46—Empty female gonotheca. Halopteris opposita (Mulder & Trebilcock). Hydrocladium with one hydrotheca. Gattya trebileocki n.sp. From holotype. Fig. 48—Whole stem. Fig, 49.—Hydrocladium with three hydrothecae. Fig. 50.—Hydrotheca, anterior view. Fig. 51.—Twin lateral nematothecae from distal end of hydrocladium, enlarged. Fig, 52,.—Median nematotheca on thecate internode, enlarged. sf hum (1938) also noted this feature in his mute- ful Erom the Sit Josenh Bunks Group, and pon. sidered that it may “constitute a distinct variety”. As the type microslide consists of a single sten) fragment 3 mm long, il scems pos- sible that the Sevth Australian maternal nay better represent The species than the type it- self. This is whe third record of Ff. apposita. (Other localities—central Vic. Sir Joseph Banks Group, S. Aust.) Gattya aghovheniaformis (Mulder & Trebil- cock, 1909), Plimularia dglaopheniaformis Mulder & ‘Trebil- cock, 1909: 32, pl. 1, fig. 7 Hafonteris agliapheniuformis (M, & T.), Shep- herd & Watson, 1970: 140, Records: R, 18-33, on Phurtuiuria procum- bens and Callophiyllix coecined, Muterial: Several colonies of a few infertile stems each. Mydrorhiza tubular. Scenis to'7 mm long, bevinning with an athecate internode with 1~3 pairs of couline nematothecae: thecate internodes. with a proximal hydrotheca, and 2 pairs of suprathecal nematothecac. Hydroctadia arising from a small apophysis behind hydro- thee», the first pair opposite, first 2 hydrocladial internodes slender, short, athecate, 0.04—-0,06 mm long, with transverse joints. distal internode longer. 0.07-0.09 mm, with 1 medinn nemato- theea. Mydratheeae 0.17-0.20 mm deep (fateral view), with broadly lobed margin 0.13-0,18 mm in diam, the anterior and posterior lateral projections curving inwards Over the aperture, Remarks: The marginal projections of the Pearson [, specimens. differ from those of P. ughophentaformis fiznured hy Mulder & Trebil- cock. Furthermore, the cauline internodes are vuriable in Jength, some heing barely long enough to accommodate the hydrotheca; those Stems with longer internodes also have a thin perisarc, are more Hexwous, and have a less deeply lohed hydrothceal margin Uhan the type. Following Millard (1962, p. 270), this and nther species with a toothed thecal margin are referred to Gatrya, Gattya balei (Bortlett, 1907). Plamularia bealei Bartlett, 1907+ 65, Mulder & Trebileack, 1909; 29, pl. 1, fizs. I-39. Hale: 1919: 344, pl. 17, fig. 6. Records; R, 14-45 mt on Metamastophara flabellata, Pterocladia lucida and Ptere- siphonia?. Afatertal: Colonies conimon. A few fertile stems with female gonophores, Sténes te 7 mm long. JEANETTE E. WATSON Cojaur—vellow, Remarks: This rare but distinctive species has not been recorded previously in S. Aust. (Other locality—eentra] Vic.) Gattya trebileocki sp, FIGS. 48-52. Tepe Matetlal and Records: Holotype. NMV (52029, microslide, G2099. preserved mate- tial, remainder of holotype culony=-R, 10— 33) m, on fragment of Caulerpa brewnil- paratypes, G2030, G2037, G2032, G2053, G2034. G2035; SAM H39, microslides—R. 10-33 m, Gn Caulerpa brownit; G2100, pre- served material, remuinder of paratype colo- nies, Description from holorype and paratypes: Uydrorhiza tubular, of same diam, as stem, embedded In the stem of the alga, Sreaw to $ mm long, proximal stem intertrode 0.70-0.75 mm long, athecate, perisare thick, with a few rough annulac constrictions, and 1-2 distal nematothecue: distal hinge joint V-shaped, Fol- lowing stem internodes alternately thecale and athecite, thecale internodes 0.25-0.45 mm long, athecate internodes 0,10--0.13 mm long. average diam. of internode 0.10 mm. Hydro- cladia arising From a short apophysis of the stem above the bydrotheca on euch cauline interrode, first pair opposite, following hydro- cladia altecnate. Hydrocladium with 1-3 hyudra- thecac, thecate and athecale internodes alter- nate, crowded. identical to cauline internodes. Athceate internodes very short. 0.04-0.06 mm long. 2 between hydrocladial apophysis and first thecate internode, distal joint oblique, the second internode with oblique distal node. and { median pematotheca; following internodes alternately alhecate and thecate, athecate inter- nodes 0.07-0.08 mm long, thecate internodes 21-029 mm long, with oblique proximal and transverse distal nodes, Ilycrothecue distal on internode, cup-shaped, U.t4-0.20 mm deep, perisare delicate. base curved, set well Jown in hydracladtum; abeauline wall 0.15-0.20 ram long, convex, thickened to hase of median nematotheca: adcauline wall shorter, 0.12-0,17 min tong (to end of lobes) not thickened. almost straight, Afargin sinuated. (20-0.25 mm in diam., with 5 lobes of which 3 wre well developed, tongue-shaped—1 unterior. peaked. tising over aperture. 2 posterior, paired, with a deep sinus between, and 2, paired. in middle of margin, broad and low in lateral view, hut often obscure Nemarothecae hithalamic, of 3 types— 1 medion, on each athecate internode (except HYDROIDS th? first hydrocladial internode), base slender, distal cup deep and rather natrow; 4 nemato- thecae on theeate internodes—! snedian, base very stout, 0.08-0.10 mm long, distal cup €x- eavated on adcatiline side, cup 0.04-0,06 mm im diam,, margin vertical. closely adpressed to hydrocladium; 2 posterior Jaterals, longer than medians, 0,08-0.10 mm long, distal cup wide and shallow, 0,05-0,08 mm in diam., slightly flattened on adcuuline side, overtopping mar- ginul lobe of hydrotheca, base slender, on a pedicel 0,06-0.08 mm long; t small median suprathecal, similar to nematotheewe on athe- cale internudes, but smaller, deeply set between the twin laterals at base of hydrotheca. Hyedranth with approx. 16 tentacles. Colous— pale yellaw. Gonotheca absent, Remarks: G. teebilgocki shows close affinity with G, aglaopheriaformis Mulder & Trebil- cock, but may be easily distinguished from, this species by the shape of the posterior marginal lohes of the hydrotheca, which in G. trebilcocki are rounded. The cups of the lateru! nemato- thecae are also much larger in G. trebilcocki. Both species occur in the same locality and over a similar depth range, but G. agiaophe- niuformisx as presently known is an epizvic spe- cies, whereas G, trebileock? has been found only on algal substrate, Both species are Tare. Pluniularin procumbens Spencer, 1891: £40, pls. 21-23, figs. 17-25. Bale, 1894: 115, pl, 5, figs Lt, 125 1914a: 29: 1915: 297, Briggs, L915: 30S, pl. LO, fig 1, Records: R, 33 m. epilithic on vertical rock faces. Material: One infertile colony 7.5 em high. Srem thick, fuscicled, growing fram a fibrous rootstock. Shore hydrocladial internodes with nematothecue ax described by Bale (19140) and Briges (1915). Remarks: Although only 1 specimen was col- lected, several mature ¢culonies of similar size and appearance were noted, The colonies arc amall io comparison with Briggs’ Tasmanian material and Spencer's material from Port Phil- lip Bay, Vic. Bale (1914a, 1915) does not give dimensions of FP. wrocwinbens from the Great Australian Bight, Phimularia asymmetrica Bale, 191 4a: 29, pl. 4, figs. 2, 3; 19152 279, FIG. 53 Records; Sin. F, 65 m, freegrowing on sandy bottom Meresial) (ne infertile colony, 30 ¢m high. Stem jong, flexuous, branched, strongly {s- cicled near base. Hydrocladia with 12-15 hydrothecae, hydrocladiai internodes with 5-7 strong septal ridges, Hydretheeae long, adnate, abcauline wall curving over distally towards hydrocladium; an indistinct intrathecal fold sometimes present about halfway aluny thecal wall. Margin with 2 broad bluntly pointed jateral Jobes, usually of the same size and shape, occasionally | lobe much more promi- nen than the other. Remarks: The Pearson |. material shows some variations compared with Bale's microslides uf -Endeavour’ material from the Great Australian Bight in the collection of the NMV. The “En- deavour’ specimens show considerubly more curvature of the distul hydrothecal abcuuline wall than the Pearson 1. material, Haye a dis- lince oblique intrathecal ridge, and a maximum of 4 septal ridges ia the internode. The mar- ginal lobes of the ‘Endeavour’ specimens sel- dom show the pronuunced degree of asym- meliry inferred from Bale’s figures of P. usyu- metrica. Furthermore, the margins of the lobes are reunded, rather than pointed, and each pair is usually the sante shape; however, as the hydrathecal margin itself is slightly oblique to the hydrocladial axis, the lobes appear asym- metrical when viewed from abeve, P. asynunetica shows g strong resemblance to «figures and description of P, Aerrmwipzé Stechow, 1909 from Japan (Bile I9l4a, p. 31) and P, #uberert var, elengata Billard, 1913 from the Indo-Pacific revion. The latter is a small species 2-3 cm high, and the hydracladtal internodes and hydrothecae appeie to be indis- inguishable from P. asymmetrica fram Pearson I, The Jess distinct intrathecal fold and more symmetrical marginal lobes of (he Pearson I, specimens tends to bridge the gap between /’. asymmetrica and Py hertwigi. Possibly all are geographical variants of the one species. Although only | colony was collected, the species was a dominant member of the seafloor community of the deeper water. Many of the ulder colonies were almost completely invested hy wa growth of a pink coloured epizoie zoun- thid, the weight of which bends the colonies over to touch the sand, This is the fourth record of Pi asvanmerrlea; other records are ulso from the Great Austra, lian Bight. Plumularia flexuosa Bale, 1894: 115, pl 5, fies. 6-10. Mulder & Trehilcock, 1916: 78 {discussiun). Stecbow, 1925: 246. Black- 183 burn, 1938: 315. Shepherd & Watson, 1970: 140. Pluntalaria pulehella (Bale), ‘Totton, 1930: 221, fig. 58. Records: R. 27-45 m, on Mvchoden carnosu. Material: A few infertile stems, Siems to 3 mm long; internodes Jong, flexuous, nutes tans- verne, 3 cauline nematothecae on an internode —?2 uxillar, and 1 proximal, exactly as des- cribed anu figured by Bale (1894) for P, (lexuutase, Reraurks; [ have examined a series of micro- slides of FP pulchella Bale, 1882, and P, flexwese in the Bale collection of the NMV. The stems of P, pulehella are robust, with several transverse cauline internodal septa, but have no cuuline nematothecae. Hydrocladia and hydrothecae are identical in both species. The yornotheca uf P, putchelle is globular, with an oblique aperture, and 4 rw of large internal submarginal weth. In PF. flexuosa, the gonotheca is clongate, twice as long as wide, and there are no submarginal teetlr. Although Bale (1894) clearly distinguished between the two species, Totton (1930) united them in P. pufchella on the grounds that “P, flexaesa . - . appears to fall well withia the Tange of variation of this species™ «ie. P. pul- chefla) as the stems of some of his material were “fine and fcxuous, while others were stout and straight", His synonymy has since heen followed by Ralph (1961b) and Millard (1957). Stem thickness and the presence or absence of cavling nematotheeae are frequently un- reliable specific criteria aniong the Plumu- Jariinae, but tuking into account the difference between the gonothecuc (unless sexual dimor- phism can he demonstrated) it scents best, fol- fowing Blackhurn (1938), tu regard the two as distinel species. Although associvted with a range of algal substrates in other localities (J.W. unpublished) P, flexnosa occurred only associated with a delicate species of the red algal genus My- chedea (nsually placed under M, carnosa in herburiu), The growth habit of the trydroid is unusual and was first poticed by Dr. H. B. S, Womersley and G, T, Kraft who supplied the following descciption. “The hydroid infests the Mychodea frands from «@ very early stage, with frands less than | cm high showing abundant hydroid stolohs. The stolons penetrate length- wise through the outer medulla of the alga. branching occasionally laterally, and producing at regular intervals through the cortex the erect, JEANETTE E. WATSON polyp-bearing axes. As the Mychodva plant de- velops.. proliferation of the hydroid stolons in the lower axis breaks down the algal tissue until the Mychodey is attached to the substrate only by a detise weft of hydroid. This may be 2-8 mm thick and a centinetre or more jung, sup- porting a much branched Mychodea plant over 20 cm long and infested throughout with the hydroid.” Plunularis spinuloga Bale, 1882: 42, pl. 15, fig. 8 I8S84: 139. pl. 12, figs, 11, 12: 1888; 783. Stechow, 1925; 246, Mallard, 1962; 301, FIGS, 54, 55 Plumidaria spinitese var. spinulosa Ralph, LY6.: 37, fig, 4. Shepherd & Watson, 1970> 140, Reeordy: R, 18-30 mm, on Lanrencia elute, Plecamium angustum, Thyroscyphis mar- ginatuy and Aglaopitenia plumosu. Material: Abunctant infertile colonies of 2 few stems ech. Hydrorhiza wide and flat with transverse dark markings. Stents to 3 mm long. intemodes of variable length, 0.17—-0,21 mm, width at node 0.02-0.04 mm Hydrovladia arising near middle of short internoues, distally On long internodes. Hydrothecae 0,16-0.18 mm deep, abcauline wall strongly convex, Terminal hydroclaciul spines well developed, varying from long und sharply pointed to blunt and barely protruding, past hydrothecal margin, Netnatathecue identical with typical form, but pedicels of the median hydrocladial nemate- thecue show considerable variation in thickness. Reniarks: The Pearson 1, matertal shows a wide variation in size of the stem internodes, position of the hydrocladial apophyses, width of the hematothecal pedicels and length of the ter- minal spine. Those hydrotheeae with more pro- hounced terminal spines arc always larger and more robust in appearance than those with the Shorier spines. Because of the variahility of length of the terminal spine, Millard (1061) n® longer recognizes the distinction. between the varicties of P, spintlosa (Le var. pypica Stechow, 1923 — var. spinulosa Ralph, 1961, and var. obtusa Stechow, 1923). The present materi] supports her view. No correlation was eviden| between stem type, substrate, or environmental conditions. Plumularia goldsteini Bale. 14982: AL, pl, 15, fig. 7: 1884; 157, pl.11, fig, 9, Records: R. 30 m, on Delisea pitlchra, Material: A few infertile stems to 3 mm lou Remiarkiy The specimens conform exsctly to the description of P. poldstein? by Bale. HYPROIDS A new record for $, Ayst. (Other loeality— Vic.) Plumularia obliqua (Johnston, 1847), Bale, I884; 138, pl 12, figs. 1-3, Blackburn, 1942. 108. ai asad obligna Johnston, 1847; 106, pl. 28, gL Records: R, 20 tm, on Melanusiephore fla bellatn; S, 30 mon Sargassum sp, Material: A few delicate infertile stems to 4 mm long. Renwarks; The material conforms to descrip- lions of PF. oblique hy Bale. Phonulmia australis Kirchenpaver, 1876. Bale. I884: 143, pl. 12, figs. 6, 7, pl. 19,, digs. 43, 44. Plumularia obligue vac. adsirelis Kirchenpauer, (876: 49, pl. 6, fig, 10, Reeaus: S$, 14 m, on the seagrass Posidonin australis. Material: Luximant infertile colonies, Stems to 4 mm long, srising from a broad fat hydro- rhiza with transverse dark markings. Remarks: The Pearson Lo material compares with Bale’s (1384) description of P. wnsyrelis. The median nematothecne are, however, not is deeply exeuvated on the adeauline side nor as closely adpressed li the bydrocludium as in his figures. ‘The aaillar monothalamic nemato- thecat are absent from many stems. Plumularia epibracteolosa o.sp. FIGS, 56-60 Type Material and Records: Holotype, NMV (42046, microslide; G210] preserved mate- nial, remainder of holotype colony; para- tvpex, G2047, G2048, G2049, G2050, G205!; SAM H37, microslides; all material —R, 50 m, on Sargassum bracteolasye, Description fren feletype and peralypen: Aydrorhiza flat, reticular, 0.25 mm wide, with pegeed borders, radiating from a digitate sto- lunic plate, Steets monosiphonic, to 2 em long, perisare thick; proximal internodes toughly un- dulated, without hydrocladia, nodes indistinct, following internodes hydrocladiate, 0.36-0.45 min iang, 0.14-1.85 mm in diam., proximal and distal nodes oblique, V-shaped. Perisarc smooth externally, internally ridged by 3—+ intemodal sepla—t above, and 1 belaw nore, 1-2 in middle of internode, ridges fewer in younger parts of stem; either absent or inci- piently developed in younger stems. Hy«lro- eludfie alternate, 1 on each slem tnternode, tn | plane, arising from a shor distal apophysis of 189 the stem, One or two hydrothecae on hydro- Cladium: hydrocladium beginning with 1, occa- sionally 2, short proximal athecate internodes 0,09-0,12 mim long, proximal, hode transverse. distal node slightly oblique; thecale inlernode 0.23-0.27 mm long, socketted into the athecate internade by a slender joint; hydrocladia below internode straight, blunt end not projecting be- yond thecal margin; 4—5 oblique interngdal sepla dividing internode into segments, 2 below median nematotheca, sloping opposite ways, and 2 below the hydrothecu. When 2 hydro- ibecae are present on hydrecladium, they are separated by 2 athecale internodes, the first short, ©.07-0.09 mm long, with transverse joints, the next 0,12-0.16 mm long, with a socketted proximal 2nd an oblique distal joint and Ll median nematotheca; both internodes without septa. Hydrothecae wide, shallow, cup- shaped, 0.15-0.17 mm deep, with a Hat base, set an the 3 strong convexitics of the hydro- cladium; abcauline wall straight, 0.11-0.13 mm long, thickened by a continuous flange of peri- sare extending the entire length of the thecate imernode; adcauline wall 0.10-0.11 mm tong, slightly convex, adnate to hydrocladium only neur base, the remainder joined to the hydro- cladium by a wedge of perisarc. Margin 0,14— 0.19 mm in diam. (laleral view), sinuated, with a thickened outwardly rolled rim, the line of the margin curved down to meet the hydro- cladium, but the aperture truncated by a deli- cate transverse shett of pensare extending across the cup 0.05 mm above adcauline wall. Neimuothecae all of similar shape and size, 0.06-0.09 mm long, bithalamic, distal cups shallow, entire, 0.03-0,04 mm in diam.; 2 cauline with slendor bases, 1 in middle of stem internode, often missing, and 1 axillar; 3 on thecate hydroclidial internodes—i, median, hase stout, cup slightly excavated on adcauline side, 2 laterals below the hydrotheca, bases stout, cups narrow, standing upright on hydro- cladium but not reaching top of transverse peri- sarcal web, One minute mamilliform pore pre- sent on the shoulder of the hydracladial apo- physis. Aydranth with approx, 24 tentacles. Gonothecue large, 1-2 on lower stem on a short pedicel arising from an old hydroela- dial apophysis, elongate oval, 138-18 mm long (including pedicel} maximum diam. 0.72— 1.02 mm (at two-thirds the distance up from pedicel) perisare delicate, smooth, or slightly uncdulated, no operculum, top closed hy a thin convex membrane. Gonophores male, mature. surrounded by a thin blastestyle Celaur— stems bright yellow, gonothecac orange. 19%) JEANETTE E. WATSON Fig, 53. Figs. 54,55. Plumularia spinulosa Bale. Fig, 54.—Part of a stem with larger hydrothecae and prom- inent terminal spines. Fig. 55,—Stem wiih smaller hydrothecae and blunt spines. Figs.. 56-60. Plurwlaria epibracteolosa n.sp, Fig, ot stem showing internadal septa a Plumularia asymmeirica Bale. Part of hydrocladium with two hydrothecae, 56.— Whole stem with stolonic plate. Fig. 57.—Part nd cauline nematothecae. Fig. 58.—Hydrocladium with two hydrothecae. Fig. 39.—Hydrotheca, dorsal view. (Figs. 46-59 drawn from holo- type). Fig. 60.—Group of two male gonophores, fram paratype, Remarks: P. epibracteoloxa is closely allied to the P. setaceoides group endemic to Australia and New Zealand, It shows some affinities with P. excavata Mulder & Trebileock, and with P. corrugatissma Mulder & Trebilcack, bug is easily distinguished from both these species by the structure of the hydrothees and from P. corrugatissma by its greater overall size. Stolonic reproduction, common among some species of the Plumulariinae, has been discussed by Billard (1904) and Gravier (1971) but has not previously been reported among the Aus- tralian members of the subfamily. Many stems of P. epibracteclosa show various stages of dis- tal enlongation into a tendril which flattens out laterally into an embryonic stolonic plate. This plate adheres to the edge of a nearby algal frond, sending out hydrorhizal filaments to form a new colony, the parent stem ‘finally breaking away. [n one case (holotype imicro- Slide) # stem has re-attached itself by the dis- tal end to the same stolonic plate, forming a closed Inup. P. epibracteolosa exhibits extreme variation in development of the cauline internodal septa. The older stems, distinguished by the thicker perisarc, are heavily internally ridged, while the younger stems have either none at all or show a gradational development between the two extremes. The presence of internodal septa has often been accepted as a diagnostic charac- ter within the Plumulariinae, but the variability of P. epibracteclasa demonstrates the un- reliability of this criterion, HYDROIDS 191 The fronds of the substrate alga Sergusrsune bracteolosum are seasonal, growing fram Sep- tember to February (Shepherd & Womersley 1970), P. epibracteolasa must therefore spread very rapidly in order to form fertile colonies within a very shurt period. This may account for the unusual propagation of the colonies by both normal growth and stolonic reproduction. the fatter method ensuring spread of the calonics from one part of an alga to another. Although the alga, §. bracteoloswn, is also very common at West I, (Shepherd & Womers- ley 1970), P. eplbracteolosa Was never recorded from this locality. At Pearson 1, the alga was restricted ta a: Jimestoie seafloor in moderate surge at a depth of 50 m, at a distance of 400 m offshore. The colonies of P. epidracrealesa accur only on the fronds, whereas Amphixbesia mlninwe var. pumileides Bale exclusively epiphytises the harder stems of the alga. Momolaria meretricit o.sp. FIGS, 61-64 Type Material and Records: Holotype, NMV G2n55, microslide; G2102, preserved material, remainder of holotype colony— R, 27-30 m, on sponge on vertical walls; paratvpes, G2054, G2055, G2056, G2057, G2058, G2059, SAM H38, microstides; G2103, G2104, preserved material, remain- der of paratype colonies—S, 18 m, on sponge on tuck walls, Description fram jelotvpe and paratypes: Aydrarhiza tubular. Stems monosiphonic, erect, straight, to 1S mm long; stem internades 0.42-- 0.51 mm long, smooth, the proximal internode beginning with a transverse joint near hase of stem, following intemodes with an oblique proximal joint, often indistinct, and a strong distal joint, 0.06-0.09 mm in diam. Aydre- cladie alternate, 1 on each internode, widely spaced, arising from a distal apophysis 0.05 inm fong. and 0,08 mm in diam, at extremity of internode, with 1, occasjonally 2 hvdro- thecve, and rarely, a secondary branch given Off behind the first hydrotheea, Hydrocladium with either L long smooth proximal athecate internode 7.14-0.19 mm long, and 0.07 mm in diam., of alternatively, 2-3 short athecate internodes 0,05-0.12 mm long. with internally Tidged perisarc, These are followed by a long thecate internode 0.30 mm long, entitely occu- pied by hydrotheca and an infrathecal cham- ber 0.10 mm Jong, terminating behind hydro- thecal margin, Mydrorhecee campanulate, O15 mm deep, at 40" to hydrocladial axis; alcauline wall rounded in lateral view, almost entirely ad- nate and immersed in internode, abcauline wall straight, expanding, contiguous with Iine of upper wall of hydrocladium, very slightly con- stricled behind margin. Murgin evérted, 0,18 mm in diam., slightly simuated, curving dows und back to adcauline wall. Nemutothecae bithalmic with slender bases and shallow distal cups partially cut away on the abcauline side, occasionally 1-2 halfway up stem internode an opposite side ta hydrocladium, and 1 axillar, 3 present on thecate internode—! median, 0.04- 0,06 mm long. adpressed to the intrathecal chamber, and 2 laterals below hydrotheca, 0.03-0.04 mm long, distal cup entire. One very prominent monothalamic mamilliform pore, with 1, sometimes 2 orifices on short tubular necks projecting from the top of the stem apophysis, Gonotleca absent. Remarks: P. meretricia, like P. epibracteclosa; shows considerable variability of features usually regarded as reliable specific criteria among the Plumulariinae, The younger stems have a smooth glassy appeurance, with long stem and hydrocladial internodes, and also have cauline nemutothecac, The stems seldom retain their chuline nematothecsac after maturity, showing only scars where the nematothecae have dropped off, Since many of the younger siems show neither scars nor nematothecae, and in some cases, the axillar nematothecae have failed to develop as well, the presence or ubsence of these structures cannot be regarded as diagnostic of the species, The mamilliform pore is however, a constant feature of all the stems, The regenerated athecate hydrocladial internodes common in some stems, mark the site of repeated hrenkage and regrowth of the hydrocladium. In these cases, a short athecate internode is first added, follawed by an em- bryenic hydrotheca and infrathecal chamber. Nematothecue bud off Tater as the hydrotheca nears maturity. The athecate intemode at this stage is without internal perisarcal ridges. These develop ag the lrydrocladium ages. P. meretricia shows some relationship with P. flexuosa Bale and P. hyalina Bale, but it ts much larger and more robust than cither of these species. Phimalaria togata o.sp. FIGS 65-67 Type Material and Records: Holotype, NMV G2060, microslide—R, 33 m, on Metavonin- lithen eharoides: paratypes. G2061, G2062, G2063, G2064, G2065, G2n6, SAM Ha4fi, 192 JEANETTE E. WATSON WW OZ wuo-| 0.25mm Figs. 61-64. Plamularia meretricia n.sp. From holotype. Fig. 61—Whole stem, Fig. 62.—Part of stem with young hydrocladium and smooth athecate internode, Fig, 63.—Older hydrocladinm with regenerated athecate internodes. Fig. 64.—Mamilliform axillar namatotheca, en- larged. Figs, 65-67, Phumiduria togata n.sp, From holotype. Fig. 65.—Part of stem. Fig. 66—Hydracladium and hydrotheca,. lateral view. Fig. 67-—Hydrotheca, anterior view, showing aperture. microslides, C2105 preserved material, re- mainder of paratype colonies—S, 30 m, on Meteagonialithan charaides. Description from holotype and paratypes: Hydrorhiza broad and flat with transverse dark markings. Stems short, to 4 mm long, mono- siphonic, flexuous; 1-3 short proximal inter- nodes with transverse nodes, following inter- nodes hydrocladiate, longer, 0,03 mm long, 0.08 mm maximum diam., smooth, proximal node transverse, distal node V-shaped, a strong transverse septum above the node. Hydrocladta short, alternate, 1 on each internode, arising from a distal apophysis, with 1 very short proximal athecate internode 0,03-0,04 mm long, followed by a longer athecate internode 0,19-0,21 mm long, curving very slightly below base of hydrotheca. Hydrothecae subglobular, 0.20-0.22. mm. high from base to crest (lateral view). 0,16-0.18 mm wide (front view). ab- cauline wall rising perpendicular to hydro- cladial axis, then curving over and hack to thecal margin; adcauline wall rounded, set well into hydrocladium, free part rising in a sinuous curve to the margin. Infrathecal chamber 0,1 1— 0.13 mm long, maximum width 0.10-0.12 mm. the proximal joimt slenderly pointed and socketted into the athecate internode. Nernato- thecae bithalamic, with slender bases, terminal cups wide, a little cut away on adcauline side: 2 cauline—1 axillar, 0.07 mm long, and 1, same as axillar, one third distance up internode, on opposite side to hydracladium; 3 bydro- cladial nematothecae, 1 median, 0.05 mm tong, HYDROIDS adpressed to. the infrathecal chamber. 2, slightly smaller, standing upright on a projection of the hydrocladium below hydrotheca, barely reach- ing thecal mirzin, and separated at the base by a Tounded prominence. of the hydrocladium. Gonotheea absent. Remarks: P. jegata is a very small species closely allied to P, fivalixe Bale, from which it may be distinguished by its smaller size, the 2 cauline nematothecac, greater curvature of the abeauline hydrothecal wall and the distinctively hooded appearance of the margin. Plamolaria australiensis o.sp. FIGS. 6871 Type Materia? and Records: Holotype, NMV G2067, microslide, G26 preserved mat- erial, remainder of holotype colony—R. 20- 25 m on sponge: paratypes. G2068, G2N69, G2070, G2071, SAM H41, microslides—R. 20-25 m, on sponge. Wescrintian from holotype and paratypes: Hydrorhiza tubular, embedded in surface of sponge. Siem monosiphenic, flexuous, to 15 mm long, petisare thick, occasionally heavily thickened at point of regeneration of a new atem from the broken butt of an old stem, Internodes variable in length, G.06—1.5 mm, nodes transverse, distinct, width at node 0.)4— 0.25 mm. proximal 24 internodes withour hydrocladia, Internodes with 6-12 cauline nematothecve scattered in 2 vertical rows in the same plane as hydrocladias axillar nemuto- thecac absent, hut 7 nematotheca usually present on intetnode just above hydrocladial apophysis; older internodes with fewer nemato- thecae. Hydraciadiq to 2 mm long, alternate to subopposite (exceptionally. lower hydro- cladia may be opposite} directed upwards in 1 plane from a short apophysis of the stem: 1—3 hydrocladia on internode. arising near Lop, middle. or hase of interaode, but this is variable; shorier internodes have fewer hydru- cladia. Hydrocladial internodes alternately athecate and thecate, the proximal athecate in- ternode with 1, occasionally 2 nemutothecae: following athecate internodes 0.27-0,32 mm long (measured along base of hydrocladium) with a transverse proximal, and strongly oblique distul joint, and 2 nemaflothecie. Thecale internodes 0.18-0.20 mm long. 0.06- 0.08 mm in diam. at transverse (distal) node, 4 maximum of 7 thecate internodes on a hydro- cladiuim, and frequently, 2 transverse intermodal septum below pedicel of lateral nematotheca. Thecate Internude with 4° nematolhecue—! Tus median, subhydrothecal, 2 lateral, and | supra- thecal. Alydrathecae asymmetrical in lateral view, wider than. deep, scoop-shapéd, set al abvut 45° to the hydrocladial axis, abcauline wall straight or very slightly concave and a iitle thickened, 0,16-0.20 mm long; adcauline wall convex, 0.13-0.19 mm long, the shallow curve of the wall contiguous with the base of the hydrotheca. Margin 0.25-0.3L mm in diam., entire, delicate, at an angle of 30° to the hy- drocladial axis. Nematorhecee bithalamic, all of similar shape and size. the cauline nemnatothecse with moderately slender bases, cups shallow, adcauline wall excavated; 2 median. nemato- thecae on athecate mlemode, similar to cauline nemiatothecae, O.07-0.08 mm long, bur with more robust bases, closely sdpressed to inter- node, the proximal nemutothecae frequently somewhat smaller than the distal. Theeate tnter- node with 1 median subhydrothecal nemato- theca, cup deeply excavated, pressed close to base of thecal wall; 2 taterals with shallow open cups 0.05-0.06 mm in diam... slighthy cnt away on udcauline side, the edge of cup not reaching thecal margin, base slender, seated on a pedicel 0.05-0.06 mm long, arising at the junction of the adcauline wail with internode; 1 small leaf shaped monothalamic suprathecal nematotheca, set deep in sinus behind hydrotheca, the aper- ture facing inwards, Gorothecaa present, male and female urising beside median subhydre- thecal nematotheca, usually tn proximal region of hydrocladium, sexes usually separate, occa- sionally both sexes present on same hydro- chidiam. Female gonotheca pear shaped, 0.18- 0.25 mm long {excluding pedicel) 0.42-0,55 mint maximum width, with 1-2 nematothecae in the basal region similar to the laterals, but lurger. Operculum a thin flap of same size a5 top of gonotheca. Male gonotheca smaller than fernale, slipper-shaped, 0,13-0.16 mm wide, with 1 proximal nematetheca, a little smaller than those on female ponotheca. No uper- culum, Pedicel a small round seginent 0.07 mm in diam, in both sexes, Remarks, P. catitraliensis is closely related to P. bedoti Billard from the Indo-pacific and P-. westnt Jarvis from South and Last Africa, but is distinguished from both these species hy the shallow scoop-shaped hydrothecae. It also shows some affinities with some Indo-Pacific members of the genus Halepteris, ea. H. buski (Balc) (a deeper water species common on the sOuthern Australian constline, alsa found at Pearson 1.}. and with A. polymorpha (Billard) in size gnd shape of the gonothetse and nema- 194 JEANEITE tothecae, general aspect of the colonies, and the tendency toward opposite branching in the hasal stem region, Aglaonhenia plumosa Bale, 1882: 37, pl. 14. fig. 6; 1884: 153, pl. 14, fig. 5. pl. 07, fig. 12 Blackburn, 1942: 110. Stechaw, 1925: 260. Ralph, 1961b: 65, fiz. 9. Shepherd & Watson, 1970; 140. Recards: R, 24-33 m, an ascidians, bryozoa- and Carpopeltis phyllaphera. Material: Sparse infertile colonies. Stems to 1 om long. Remarks: The stems are short, with closely set hydrocladia and robust hydrothecae, features characteristic. in this species, of an ocean en- vironment. Thecocarpus divaricatus (Busk) var. maccoyi (Bale. 1884: 162, pl. 15. fig, 7 pl. 17, fig, 7), 1915: 312, pl. 1. “Avlaophenia maccoyi Bale, 1882: 36, pl. 14, fig. 2. Blackhiirn, 1942: 110, Thececarpus divaricates CBusk). Shepherd & Watson, 1970: 140, Records: R, 23-45 m; §, 4-12 m, on Meta- goniolithon charoides, Plocamium cartila- gine, Acrocarpia paniculata and Zonaria splralls. Material; Luxuriant fertile colonies. Srenrs short, ta 4 cm long, given off in groups from a winding hydrorhiza, Proximal region of stem without hydrocladia, lightly fascicled, some af the supplementary tubes running up the main stem for u short distance then branching. off. Aydrocladia 4 mim long. Hydrathecue close-set at 45° to hydroclacial axis, marginal teeth deeply cut, the second anterior pair outwardly bent, the unpaired anterior tooth — well developed, the hatchet shape becoming mare pronounced distally ylong the branch, Median nemidothece vatlable in length, just over- tapping margin in proximi region af hydro- eladium, increasing to twice the height of hydrathecs distally, standing well out fram: the margin. the terminal aperture af the sume time broadening out into 2 lobes. Corhulae immature, with 4-11 pairs of gonohydroctladia; immature gonophores in corbulae with more than 10 Ieafiels. Cofour—variable, light to dark brown. Thecocarpos divarticatus {Busk) var, brigesi Bale. 1926: 22. fix. 5. Aglaophenia divaricatr (Busk). 162, pl. 05, fig. 8, pl, 17, fig. 7, Balu. 1884: E. WATSON Aglaophenic ditaricata vay. acanthocarpa’ Bale, 1915 FIZ. Records: R, 24-33; 8. 18 m, on fragments of red alge and Canlerpe simpliciusente: Stn. F, 65 m, on Syniplectoseyphus subdicho- TOTTER, Material> A few infertile stems in each colony. Srenis to 1.5 em long, unbranched, mono- siphonic, given olf singly from a winding hydrorhiza, Hydrocladia flexuous. distant, cach internode with 2 distinct seplu. Aydrothecar with 4 pairs of marginal tecth. similar in shape and size, the median anterior tooth net well developed. Median nemutoiheca slightly lenger than hydrotheca, following curve of the ab- cauline wall, becoming erect just behind mar- gin. terminal orifice round. in some cases broadening tnto Iteral lobes; canting nemuato- thecae larger than laterals, bent around stem, orifice facing posteriorly, (nfaue—hrown. Remarks: This is the first record of the vat. hriggsi from §, Aust, (Other locality. Port Jackson, N.S.W.). Thecocarpus divaricatus (Busk} var. cystifera Bale, 19157 314, FIG. 72 Records R, 24-33 m, 8, 24 m, epillthle on vertical rock faces, Material: Abundant. infertile calonias. Colonies. of 1-3 stems to 10 cm bigh, growing from a small Common fibrous rootstock, Stenry thick. woody. brittle, lightly fascicled, the poly- siphonic tuhes running up the main stem and branchng out alternately in one plane, giving the colony a distinct "front and back” aspect Proximal region of stem barc, showing sears where brinches and hydrocladia have dropped off. Aydrocladia to 13 mm long. Hvdrethecie set al an angle of 45° to hvclrocladial axis; mar- final teeth of similar size. evenly spaced. the sinus between often wide wnd shallow. Median neinatorheca following curve of the abcaulinc wall. Lenminating just below margin, terminal orifice round; cauline nematothccae large, ege- shaped, Colonr—iight brown, Remarks: Bale (1915) described; but did not figure the variety eystifera. distinguishing it from other varieties of T. divaricatus only on the presence of the enlarged caine nemato- thecae, Remarks an the varieties af T. divaricatus: Tt is of interest that the 3 varieties of this species, recognized by Bale, ale recorded for the first lime fram one Jocality, 7. muceovi ELYDROIDS. has previously been reported from various localities along the Victorian coastline (Bale 1884) and from South Australia (Blackburn 1942. Shepherd & Watson 1970). T. cystifera has been recorded only from) South Australia (Bale 1915) and 7. hriggsi only from New South Wales (Bale 1926). The only informa- tion hitherto available on the macrostructures of the hydrocaulus is given by Bale (1884) who described the typical form as having “numerous divergent branches and very dark colour” and the var. meccoyi as a “dwarf form”. (The larger “typical” form, ic. A, divaricata Busk, a very common and distinctive species of the south-eastern Australian coasi- line, was not found al Pearson [., despite careful search). The distinction between the varieties has therefore Jargely rested on micro- structures alone. 195 Although some intergradation in structure does exist between the varieties, the material from Pearson I. now enables a clear distinction to be made in both micro- and maero-siruc- lures, as Well as environmental preferences. T- maccoyi and T, brigyysi, because of their simi- larity in size and overlap ot substrate prefer- ences, are difficult to dlistinguish in the field, but they are easily separated on micro-structures: T. cystifera although unmistakable im size and growth habit, has hydrothecae almost identical with those of I. briggst. T. maccoyi was the only Variety fertile at the time of collection. The gradation in micro- and macro-structures, habit, and apparent difference in fertile season of the varieties, suggests incipient speciation within the 2. divaricamus group, Distinguishing features between the varieties from Pearson I, aré tabulated below. T. maceeyi medium, 4<¢m lightly fascieled, branched twice length of hydra- theca, orifice lobed Stem length Colony Mesial nematotheca Cauline nematotheca normal size, shape Marginal teeth sharp, deep Habit epiphytic T. cystifera large, 10cm T. briggst small, 1.5 cm unfascicled, unbranched to hydrothecal margin, orifice round to lobed Fascicled. braiched tn } plane to hydrothecal margin, orifice round normal size, shape, large, ovale facing posteriorly sharp, deep wide, shallow epiphytic-epizoic epilithic Lytnearpus mulderi (Bartlett, 1907), FIG, 73 Aplaophenia muldert Bartlett, 1907; 66, Mulder & Trebilcock, 1916: 73, pl, 10, fiz. 3- Records: Among algae; no other data re- corded. Material: A fragment | em long, the distal end of a fertile stem. The specimen conforms. to vescriplions of Bartlett und Mulder & Trebil- cock. Gonosome comprising 2 gonophores—t male and 1 female, in an open corbula arising from a primary hydrocladium. Primary hydro- ciasdium with thecate proximal internode, fol- towed by a swollen internode hearing 3. nema- tocladia and gonophores. Nematocladia 0.75— (.84 mm long (but may be broken) each bear- ing a single row of nematothecae. Ganothecae round, laterally compressed; female, 135 mm in diam., slightly larger than male, packed with mature ova, blaslostyle almost filling ganothecal cavity: male gonophore surrounded by a blasta- styit o£ the samé shape, but of smaller size than the female. Remarks; This is the first record of a species referahle 10 the genus Lytecarpuy from southern Australian waters. As earlier descrip- tions wete derived from fragmentary infertile material, it was assumed, in the absence of the gonosome, to belong to the closely related genus Apglaophenia, common in southern Aus- tralia, This is the vhird record of this rare but distinctive species, and the first record for S, Aust, (Other locality—Bream Creek, Vic.). Halicornopsis elegans (Lamarck, 1816). Bale, tda: 56; 1915: 303. Briges, 1914: 309, Blackburn, 1942; 107. Shepherd & Watson, 1970; 140, Plamiularia elegans Lamarck, 1816; 129, Halicornopsis aviculuris Bale, 1882: 26, pl. 13, fig. 3; 1X84: 185, pl. 10, figs. 1. 2. pl 19, fig. 32. Records: R, 33 m, epilithie, and on bryozoa and red algae. Material: One small infertile colony. Stems Lo 3.cm long. branched, Remarks: Vhe colonics were comparatively small and the individuyl stems short for the species, JEANETTE E. WATSON 196 O.5mm wus 'o wusz:-O wuUgrd wu Q-2 HYDROIDS (97 Halicornaria longirostr® (Kirchenpauer, 1872). Bale, 1884: [8]. pl. 13, fig. 7, pl. 16, fig. 3, pl. 19, fig. 30. Shepherd & Watson, 1970; 140. Apgloophenia flongirastris Kirchenpauer, 28, pl. 1, fig. 19, pl. 5, Ng. 20, Records: KR, 18-33 m, cpilithic on rock walls, oo Herainunia memus, red algae, and bryo- zoa, Material: Abundant infertile colonies, Stems to 7 om long. with 1-2 proximal branches. Colour —pale straw colour Remarks! The colonies fall into 2 groups— those with long stems, and those with short stems, The larger colonies, comprising clusters mt longer stems (up to 7 cm) were either epi- lithic or epizoic, whereas the shorter stems Cup tu 3 cm) growmg singly, were epiphytic on algac. There is no difference in micro-structures between these two ecologically distinc, stem types. Halicornaria prolifera Bale, 1882: 34, pl. 14, fiz. 5; 1884: 183, pl). 14, fig. 1, pl. 16, fig, 10, Ritchie, 1911; 858, pl, 85. figs, 2, 3. Records: R, 30 m, epilithic. Marerials One infertile unbranched colony. Stem & cm high, Aydrocledia 0.7 mm long. given off at un acute angle to the stem. Anterior and posterior cauline nemutothecae with 3, somerimes 4 orifices, median hydrocladial nematotheca extending just below thecal mar- gin. Marginal teeth shallowly scalloped, the middle pair slightly everted. Remarks: The specimen agrees in most respects with Bale’s description of H. prelifera, except that the median nematothecue ae a little shorter than those described by Bale, and all the cauline nematothecae have 3 orifices. The hydrothecal margin is circular in anterior view, similar to Ritchic’s (1911) specimens. This is the first record ol H. prolifera from S. Aust, (Other localities—N-S,W. and Vic.) Halicornaria auren 1sp- 1&72: material, remainder of holotype colony—R, 33 m, epilithic on rock walls; paratypes, Gi089, microslide, G2108, preserved material, remainder of colony—R, 33 m, epilithic; G2090, microslide, G2109, pre- served material, remainder of colony—R, 27-30 m, epilithic on rock walls; SAM microslide. Dexeription from holotype: Colony 6 em high, growing from a smail fibrous rootstock, Sent monosiphonic, lower stem 1 min in diam,, athe- cute. divided inte internodes, nodes transverse, proximal intemodes wath circular pits where cauline nemuiethecue huve dropped off. First branch 2 cm abuve base, all branching there- after dichotomous, at an angle of about 40°, the branches becoming somewhat convergent distally, then rebranching, Branching repeated 6-7 Times, always in the une plane. Branch internodes short, 0.60-0.69 mm, divided hy indistinct transverse nodes, diam, at node, 0.66-0.84 mm. AHydraciadi2 to 5 mm long, alternate, 2 on an internode, given olf after first branching of main stem, standing out stiffly at an acute angle from the branch, giving the colony a decidedly “front and back” aspect. Hydrocladial internudes 0.28-0.31 mm long, nodes almost perpendicular to the axis, indis- tinct, no internodal septa, Hydrothecae squat, set. at an angle of 50° to hydrocladium, 0.23— 0.26 mm deep, filling internode; adcauline wall straight, fixed part 0.12-0.14 mm long, free part 0.03-0.05 mm long; abcauline wall 0,t7— 0.19 mm long, divided in the middle by a long intrathecal ridge projecting slightly forward more than half way across thecal cavity; base of bydrotheca flat, with a small knot of den- ticles on the adcauline side marking the hydro- pore, Margin (.17-),29 mm in diarm., with 8 teeth—3. pairs of prominent blunily pointed teeth, the middle pair the longest, outwardly hent, the anterior pair erect. the posterior pair slightly everted: 1 low postenor tooth, often chsolete. and 1 small anterior tooth below the median nematotheca. Median nematothecue almost twice the height of the hydrotheca, 0.28-0.40 mm jong, 0.05-0.07 mm wide at FIGS. 74-76 Type Moterial and Records; Holotype, NMV G2088, microslide; G2107. preserved Figs, #8-71. Plumularia australiensis usp. Fig. 6%.—Part of stem. Fig, 69.—Part of hydrocladium, en- larged. Fig. 70.—Male gonotbeca, (Figs. 68-70 from holotype), Fig, 71—Female eonp- theca, from paratype. Fig. 72 to shaw cauline nematothecae. Fig 73. Figs. 74-76 Thecoéarpus divaricatus var, cystifere. Bale. Part. of branch with hydrocladia removed Lytocarpus mulderi (Bartlett), Open corbula with male and female gonophores. . Halicorseria aurea op. From holetype, Fig, 74.—Part of stem wilh hydrocladia on one cide removed ta show cauline nematothecae, Fle, 75. —Hydrothecae. anterior view, Fig, 76,.—Hydrothecsa¢, Jatersl view- 198 JEANETTE EB, WATSON hase, tapering distally and inclined forward, lerminal apeyture small, circular, lateral aper- ture distinct, Lateral neiatothecae small, 0,1 1— O13 mm long, saccate, not reaching thecal margin, | small terminal aperture on aw short outwardly turned neck, and 1 lateral aperture facing inward towards the hydrotheca. Gono- theca absent. Colaur—amber, Remarks: The matginal thecal teeth exhibit the variations in Jength and shape characteristic of Halicorrnaria. The teeth are normally long, the middle tooth being the longest of the 3 on each side. The median nematothecue are all of newly equal size, and show little tendency towards increase in length in the distal region of the hydrocladium. A. aurea resembles 2 other southern Austra- lian species of Hallcornaria—H. superba Bale, and #f.. baileyi Bale. Tt differs from the former in minor micro-structures, the marginal thecal teeth of H. superba beng sharper and narrower than those of I, aurea, the median nematu- theca of H. superba is larger, and the lateral nematothecae have 1 Jateral and 2 terminal uperiures. In A. aurea the Ioterals have only 2 apertures, i facing inward and the other out- ward; as they are very small they are sometimes difficult to distinguish, In mucroe-structures, however, H, aurea is easily distinguished from Hi. superba, whose stems are long, gracefully pluiyosc, and yellow-green in colour. In size, growth hubit, and colour. the colonies af H. area are indistinguishable from AH. baileyi, ‘they are however, quite different in micro. structures, ff, aurea is an abundant species on tock faces exposed to surge. Acknowledgments Jam grateful to the Royal Society of South Australia and the Department of Fisheries und Fiuuna Conservation of South Australia for the Opportunity to participate in the Pearson Island Expeuition; to the Director and Dr. B. J. Smith of the National Museum of Victoria, Mel- boume. Jor use of facilities and equipment; to Dr. H. B.S. Womersley, Botany Department. University of Adelaide, for identificaGon and information on algne, and helpful.advice; to the Australian Museum for the loan of material, and to Mr. S.A. Shepherd for criticisin of the manuseript. Thanks are due to Normalair Gar- fet, Melbourne, for the loan of a compressor. L especially acknowledge the unfailing help and enthusiasm of my diving companions, Scoresby A, Shepherd, and John O, Ottoway. Expenses of this study were partly met by a gruna fram the Science & Industry Endowment Fund, CSIRO, References ALEMAM, G, 7, (1872).—"A Monograph of the Gymnaublastic or Tubalarian Mydroids", Ray, Soe. 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Afr. Mus. 5019). 165-194. Mitraww, N. A. H. (1968}).—South African hy- droids from Dr Th. Mortensen's Java—Sauth Africa expedition, 1929-7930. Vidensk. Medde, dansk naturh, Foren, 131, 251-288, Mutpex, J. F. & Tnestrcock, R. EB. (1909). - Notes on Victorian hydroida with descriptions gt ¢" species. Geelong Nat, 4, 2m) ser, I= 20 Mucoer, J, F. & Treninencx, R. FE, (1910),— Notes on Victorian hydroida with description of new species. Geelong Naf. 4, 2nd ser., 115-124, Pls. WT, U1. Mutopsr, J. F., & Tresmcocrn, R. FR, (1914a).— Victorian hydroida with description of new species, Part IN, Geelong Nat, 6(1), 6-15, Pls. I-Ti. Mutper, J. F.. & Trepicock, R. F. (19)4h).— Victorian hydroida with description of new species. Part IV. Geelong Nar. 6(2), 38-47, Pis, ['V—-VI, Mueoer, J. F;, & Tresocock, R. E. (1915).— Victorian bydroida with description of new species. Geelong Nat. 6(3), 51-59, Pls, VIi- Mutoper, J. F., .& Tresmoocr, R. FE. (1916)— Victorian hydroida. Geelong Net. 6(4), 73- 84. Pls. X, XT. NisHmamea. M. (1967).—Observations on the algal selection by the larvae of Sertularella nituren- sis in nature. Bull, mar. Biol. Stat. Asamushi 13, 35-48. Pennycuk. P, R. (1959).—Fannistic records from Queensland. Part V. Marine and brackish water hydroids, Pap. Dep. Zaal. Univ. Od (6), 141-210, RALpH, Patricia M, (1953).— A gnide to the athe- cate (gymnoblastic) hydroids and medusue of New Zealand, Twatara 5, 59-75, RarPuH- Patricia M. (1958) —New Zealind thecate hydroids, Part Il, Families Lafoeidae, Lineo- lariidae. Haleciidae and Syntheciidae. Trams, R. Soe. N.Z. 85(2), 301-356. Rafer, Patricia M. (1961a)—New Zealand thecaie hydroids,. Part TIT. Family Sertularii- dae. Trans. R, Soc. N.Z, 88(4), 749-838. RacrpH. Patricia M. (196lb).-New Zealand thecate hydroids, Part [V. Plumulariidae.. Trans. R. Soc. N.Z (a.s.) 1(3.), 19-74, Rarpa, Patricia M, (1940),—Port Phillip Survey- Hydroida. Mem. nai. Muy. Viet. 27, 157-166. Rees, W. J, & Trrsrieto, Sarah (1965)—The hydroid collection of James Ritchie. Proce. R- Soc, Edinhureh 69(1-2), 34-220, Rircure, J. (1911)—Hydrozoa (Hydroid zoo- phytes. and Stylasterina) of the “Thetis” ex- edition. Mem. Ant. Mus. 4, 807-869, Pls, -_XXNTIV-LXXRKIX. SHEPHERD, S. A., & WwTson, Jeanctte E. (1970). —The sublittoral ecology of West Tsland, South Australia. 2. The ussociation between hydroids und algal substrate. Trany. R. Sac. NS. Aust, M4, 139-146, Strecnow, E. JEANETTE E. WATSON SHEMHERD, 5. A., & WomersLey, H. B. §. (1970), —The sublittaral ecology of West Island, South Australia. I, Environmental features and the algal ecology. Trans. R. Sac, S$. Anst. 94_ 105-138. SHepHero, 'S. A., & Womersity, H. B.S. (197]), —Pearson Island Expedition, 1969. 7. The sub-tidal ecology of benthic algae. Trany, R- Soc, §. Aust. 95(3). 155-167. Spencer. W. B. (1891)..-On the Structure of Ceratella fiisca (Gtay). Trans. R. Sac. Vier. 2(2), 8-24, Pls, 2-3a. Stecnow, FE. (1919)—7ur Kenntnis der Hy- droidenfauna des Mittelmeeres, Ameérikas Limit, enidere Gebeite. Zool, Jh. (Sysi.) 42, 1-172, Stecnow, E. (1921)—Ueher Hydroiden der Deutschen Tiefsee—Expedition, nebst Bemer- kungen uber einge andre Formeén. Zool Anz. 53, 223-236. (1923).—Nene Hydroiden der Deutschen Tiefsee—Expedition nebst Bermer- kongen ther emige andre Formen, Zod, Anz. 56, 1-20. Srecnow, E. (1924).—Diagnasen neuer Hy- droiden aus Australicn. Zool. Anz. 59, 57-69, StecHow, E. (1925).—Hydroiden von West-und Stidwestaustralién nach den Sammiungen von Prof, Dr. Michaelsen und Prof. Dr, Hartmeyer, Zool. Jaltrh, Abt. f. Syst. 50. 191-269. Stecnow, E. (1926)—E#inige neuer Hydroiden aus verschiedenen Mecresgebieten, Zool, Aucz. 68. 96-108. Totton. A. K. (1930).—Coelenterata, Part V, Hydroida. Brit. Antarct. "Terra Nova” Exp, 1910, 515), 131-252. 3 pls. THompson, DA. W. (1879).—On some new ond rare. Hydroid Zoophytes (Sertulariidae and Thuiariidae) from Australia and New 7en- land, Ann, Mag, Nat. Hist. (ser. 5), 3. 97- 114, Pls, 16-19. Tresiecocx, R. F, (192%) —Notes on New Zéa- land Hydroida. Prac. R. Soc. Vict, Ons.), 41(1), 1-31, Pls, 1-7. Watson, Jeanette BE. (1969}—Scoreshia, a new hydroid genus from South Australian waters. Trans, R, Sac. S. Aust. 93, 111-117. Warson, Teanette KE. & Urinomr, H. (1971)— Port Phillip Bay Survey 2. Occurrence of Solanderia fusca (Gray, 1868) (Hydrozoa) in Port Phillip Bay, Victoria. Merz. nat. Mus, Vict, 32. 19-20. WomersLey, H. B. S.. & Exmonos, S, J, (1958). —A general account of the intertidal ecology of South Australian coasts. Amy. J, pen. freshw. Rey, 9, 217-260, PEARSON ISLAND EXPEDITION 19697-10. OPISTHOBRANCHS BY ROBERT BURNS* Summary BURN, R. (1973). -Pearson Island Expedition 1969.-10. Opisthobranchs. Trans. R. Soc. S. Aust. 97(3), 201-205, 31 August, 1973. Three species of opisthobranch molluscs from Pearson I., Notarchus indicus (Schweigger), Aporodoris merria Burn n.sp. and Goniodoris meracula Burn, and one species from nearby Flinders I., Sagaminopteron ornatum Tokioka & Baba, are new records for South Australia. Additional distributional data are given for G. meracula and S. ornatum. PEARSON ISLAND EXPEDITION 1969+—10. OPISTHOBRANCHS by Rogert Burn* Summary Burn, R. (1973).—Pearson Island Expedition 1969.—10. Opisthobranchs. Trans. R- Soc. 8. Aust. 97(3), 201-205, 31 August, 1973. Three species of opisthobranch molluscs from Pearson I., Notarchus indicus (Schweigger), Aperodoris merria Burn usp, and Goniodoris meracula Burn, and one species from nearby Flinders I, Sagaminopteroa ornatum Tokioka & Baba, are new records for South Aus- tralia. Additional distributional data are given for G. meracula and S. ornatrm. Introduction The opisthobranch molluscan fauna of South Australia is relatively poorly known, especially with regard to the naked or “nudibranch” species Of the western coastline of the State.. Thus it is not unexpected that any collection from this atea should contain new species and new records, Three species described in this paper were collected during the 1969 Pearson Island Ex- pedition, organized by the Royal Society of South Australia and the South Australian De- partment of Fisheries and Fauna Conservation. The Pearson Islands are the small southern part of the Investigator Group at the eastern end of the Great Australian Bight. The largest island, Pearson I, is about 162 hectares in extent, but the others are much smaller; they lic 64 km southwest of Elliston. The fourth species im this paper was collected during a stop-over by the Expedition at Flinders T., a large island that forms the northern part of the Investigator Group. The specimens have been deposited in the National Museum of Victoria, Melbourne (NMV). Order CEPHALASPIDEA Superfamily PHILINACEA Family GASTROPTERIDAE Sagaminopteron ornatum Tokoika & Baba, 1964: 218. Bennett, 1966: pls. 1, 120b. Baba, 1970: 47. FIGS. 1-2 Material: Flinders I, Jan, 1969; 2 spect- mens from 10 m on C'ystophora on vertical rock face in fair surge (NMV. F27399). The living animals were reported as “hright blue under water, parapodia edged with bright yellow”. They are now colourless and 12 and 9 mm long, 6 and 5 mm broad. When alive, the larger animal was almost 25 mm long. The one major difference between the Japanese type specimens and Australian material (Fig. 1) is the presence of a relatively large strong shell in the mantle cavity beneath the posterior caudal lobe of the body. The shell of the larger Flinders J, specimen (Fig. 2) is 2 mm Jong by 1.4 mm wide, and is white with a yellowish transparent protoconch, the interior of which is open. The shell of a Lord Howe I, specimen is 2.4 x 1.7 mm, one from Cockburn Sound, Western Australia, is 2.1 x 1.6 mm, and another from Heron I.. Queens- Jand, is almost 4 mm long, Tt must be assumed that the shells of the Japanese types dissolved during fixation and preservation. Though hitherto unrecorded, Sagaminap- teron ornatum 3s ia fairly common species in eastern and southern Australia. Specimens examined by the writer are: 1. Lord Howe 1L—Middle Beach, Jan. 1959, R. R. Rlackwood, 1 specimen (NMY, F20717). 2. Queensland.—Heron 1., Capricorn Group, Aug. 1965, I. Bennett, | specimen. Humpty * Honorary Associate, National Museum of Victoria, Melbourne, Vic. 3006. + Other accounts of the geomorphology and biology of the Pearson Islands are given in Volume 95, Part 3 (1971) of the Transactions, as wel] as in the present Part, 22 R. BURN L, Keppel Group, Supt, 1969, N, Coleman, These specimens were collected from be- 1 specimen. tween the intertidal zone and 20 m depth, 3. New South Wales —Angourie, Aug. 1966, from heneath boulders, from brown algae, A, A. Cameron, 1 specimen. Minnie or from grey branching sponges. They have Waters, Jan, 1963, G. Biddle, 1 specimen. often been observed, in rock pools and deeper Bawley Point, near Ulladulla, Dec. 1963, water, to swim with a rapid synchronous un- f. Bennett, 3 specimens. dulution of the parapodia. 4, Victoria—Bear Gully, Waratah Bay, April 1970, f. Marrow, 6 specimens. Order ANASPIDEA 5, South Australia—Port Noarlunga, Feb, Family APLYSHDAK 1966, R, Balfour, 1 specimen (SAM, Notarchus indicus Schweigger, 1820. Bergh, 14888). Anxious Bay, Dec. 1968, T- 1902: 349. Engel, 1936; 113. Eales, Castle, 1 specimen. 1944: 12. 6, Western Australia—West of Carnac |,, FIGS. 3-6 Cockburn Sound, Feb. 1971, B. R. Wilsan Material; Pearson [., Jan. 1969, 1 specimen & N. Coleman, 4 specimens (WAM, 474- from algae on horizontal faces at 26 m 71). (NMV, F27401). Figs, 1-2. Sagaminopteron ornatum. Fig. 1— Dorsal view of a 20 mm long specimen from Port Noarlunga, S. Aust., from a sketch by Dr Helene M, Laws, Curator of Marine Inverte- brates, South Australian Museum. Fig, 2—Shell from larger Flinders I. specimen, dimen- sions 2 x 1.4 mm. Figs. 3-6. Notarchus indicus. Fig. 3.—Diagram of mantle cayity and aperture (a—anus, b—dgill, c—pigment gland, d—mantle apertute, e—opaline gland), Fig. 4—Radular teeth, Fig. 5,— Jaw element. Fig. 6—Male copulatory organ (p—penis, r—retractar muscles, s—sheath, t—seminal groove). OPISTHOBRANCHS The colourless preserved specimen is 5 mm jong, 3,5 mm wide and 3 mm high, Fhe head and neck are invaginated into the smooth vis- ceral hump. The 1 mm long mantle aperture (Fig, 30), of che usual external shape, is placed well forward, The large mantle cavity, not yet pervious with the dorsal mantle aperture, con- tains a small lobulated gill (Fig. 3b), a Jong loop of the intestine terminating well behind the gill stem at the anus (Fig. 3a), a long curved granular pigment gland (Fig. 3c}, and a small white opaline gland (Fig. 3e). No genital groove is apparent, Short stumpy thinophores with deep lateral grooves project fram the head, and a small rounded knob-like oral tentacle occurs ether side of the mouth. The jaw elements (Fig. 3) are narrowest just below the serrulate distal end. The hyaline radula (Fig. 4) is almost 2 mm long with 21 rows of 20.1.20 teeth. The rhachidian tooth is slender with sharply pointed cusp and a short denticle each side. The lobulate first lateral tooth has onc inner and two outer denticles, and the next six teeth have op to lwo inner and four outer denticles, The succeeding teeth have longer cusps with up to five inner and nine outer denticles at the third or fourth tooth from the margin, The murginal tooth has one innee denticle well back from the tip and about four incipient outer denlicles, The minitile male copulatory organ (Fig. 6) agrees exactly with the figure for Mauritius specimens given by Engel (1936, p. [16, fig. 4) with the exception that the grooved smooth penis hys not as many spiral turns. Discusion: The descriptions by Bergh (1902) and Engel (1936) of specimens From Mauri- tius, plus that of a specimen from Zanzibar (Eales 1944), satisfactorily diagnose Nofar- chax indicus, The spiral unarmed penis justi- fies the identification of thts very small Pear- son T. specimen. The smal) number of lateral teeth ¢20), the marginals of which are not slender and smooth, does not agree with the above three descriptions where the lateral teeth number 43-45, 33 and 32 respectively and the marginals are long: slender and smooth. How- ever, the Pearson I. specimen is probably a juvenile in which the radula has not attained the full complement of teeth nor the penis the full number of turns, Notarchus indicus has a wide Indo-west Pacific tropical and subtropical distribution, and hag been recorded from Sydney Harbour, New South Wales (Engel 1936, p. 119}. It as w new record for South Australia, 205 Order DORIDACEA Tribe CRYPTOBRANCHIA Family DORIDIDAE Aporodorls merria n.sp. FIGS. 7-11 Material: Pearson J., Jan. 1969, | specimen (holotype) from red algae at 52 m (NMV, F27402). The alcohol preserved specimen (Fig. 7) is dull orange-fawn in colour. It measures & mm long, 5 mm broad and 3.5 mm high. The notum is covered with various sized tubercles (Fig, 86), the largest. of Which are somewhiut flay clavate and up te 0.6 mm in diam, All tubercles have projecting angles both laterally and dorsally. Bundles of spicules strengthen each angle. The rhinophorsl cavities are pro- tected by four tubercles; a large one ot each side, a sniall one in front and a small one be- hind each cavity (Fig. 8a). The branchial cavity has nine or ten lappet-like tubercles of various sizes along the margin (Fig, 8¢); these tubercles are Up Lo 1 mm tong and 0.8 mm wide and have small projecting angles or Points on the onter or dorsal face only. The thick fleshy hyponotum is narrower than the foot (Pig. 9), from which it is separated laterally by little more than the foot margin. The genital aperture opens in the middle width of the hyponotum. The lamellate Thinophores are completely withdrawn. There are five mul- tipinnate gills. The head (Fig, 10) lies within a deep concavity of the anterior hyponoeuim, with a grooved ridge-like oral tentacle at each side of the mouth. The broad font is anteriorly truncate with the upper lamina leading into the head cavity where it. is notched, The tail is thin and broadly rounded. The thick labial cuticle ts smooth. The radula is 1.7 mm long and 1.4 mm wide. It has 40 rows of 41 teeth per half row, All teeth are hook-shaped und bear a single outer denticle beside the cusp, except for the two marginals which have If or more comb-like denticles (Pig. 11). The brittle genital organs could not be examined satisfactorily, The whitish sompulla is long and winding. The yellow vas deferens is short and twisting; and terminates in an un- armed penial sheath without penial papilla. Discussion: The angular, flattened, clavate tubercles of the notam and the single promin- ent outer denticle of the lateral radular teeth separate A. nrerria from other species of Aporodoriy Ihering, (886, The unarmed penis of the new species is similar to that of THor- 204 disa Bergh. 1877, but in that genus the Jateral teeth are smooth. The radula is also similar to that of Taringa Marcus, 1955, but the un- armed penis of A, #erria contrasts with the cuticularized penial papilla and spines of the former genus. The concavity of the head and the large lappet-like tubercles of the branchial margin ure further distinguishing characters, The rela- tively flat underside of the specimen, with the head parts recessed, suggests that A. mierria has unusual feeding preferences. The specific name is derived from “merri”, an Australian Aboriginal word meaning stones, in allusion to the notal tubercles. Figs. R. BURN Tribe PHANEROBRANCHIA Superfamily SUCTORIA Family GONIODORIDIDAE Goniodoris meracula Burn, 1958: 27; 1966: 227, FIGS, 12-13 Material: Off Dorothee, Jan. 1969, 1 speci- men [rom algae at 65 m (NMV, F27400). The colourless preserved specimen measures 7.5 mam long and 3,5 mm broad. Living speci- mens (Fig. 12) are usually yellowish with darker brown mottling. Important characters for the identification of this species are the smooth body, the high notal flange open be- ra lateral = 7-11. Aporodoris merria. Fig, 7—Dorsal view of preserved holotype. Fig. §—Notal tubercles from rhinophoral cavity (a), middle of the notum (b), and branchial margin (c). Fig. 9.—Anferior hyponotum. Fig, 10.—Detail of head with anterior foot folded down, Fig, 11.—Radular teeth, Figs. 12-13. Gonivdoriy meracuta. Fig. 12.—Dorsal view of an $ inm long specimen from Point Dan- ger, Torquay, Vic. Fig. 13—Half row of radular teeth from Sydney Harbour specimen, OPISTHOBRANCHS hind the gills, the short caudal crest, and the seven gills. The species has been very rarely collected. The holotype was found eating into a yellow- ish compound ascidian beneath a. stone at Point Danger, Torquay, Victoria (Burn 1958), and a second specimen was recorded from Portsea Pier, Port Phillip Bay (Burn 1966). A third specimen was taken by the writer at Point Danger, Torquay, Dec, 1963, where it was crawling on brown algae. Three specimens (Australian Museum, C312), dredged in Sydney Harbour, New South Wales, on |! June 1892, are a new record for that State and the only other speci- mens known to date. Each measures 10.5 mm 205 long by 5.5 mm wide. The radula (Fig. 13) of one specimen has the formula 26 x 1,1,0.1.1; the lateral tooth is strongly hooked with smooth cusp, while the marginal tooth has much the same shape and is about half. the size of the lateral tooth. Goniodoris meracula is a new record for South Australia. Acknowledgements The writer is indebted to Mrs Jeanette E. Watson, Honorary Associate, National Museum of Victoria, Melbourne, for the col- lection of, and the ficld notes on, the Pearson I. opisthobranchs. This research has been aided by a grant from the Science and Industry En- dowment Fund, C.S.I.R.O., Canberra. References Baba, K. (1970) —List of the Gastropteridae and Runcinidae of Japan. Collecting and Breed- ing, 32(2), 46-48 (in Japanese). Bennetr, EL (1966).—"“The Fringe of the Sea.” (Rigby: Adelaide, ) BercH, R. (1902).—Malacologische Unter- suchungen. Jn C. Semper (Ed.), “Reisen im Archipel der Philippinen", Vol. 7, pp. 313- 382, plates 25-29. Burn, R. (1958).—Forther Victorian Opistho- branchia. J. Malac, Soc, Aust. 1(2), 20-36. Burn, R. (1966).—Port Phillip Survey 1957- 1963: Ophbisthobranchia. Mem. natn. Mus. Vict. 27, 265-288. Eaues, N. B. (1944).—Aplysiids from the Indian Ocean, etc. Proc, Malac. Soc. Lond, 26, 1= ENGEL, H. (1936).—Some additions to our know- ledge of the genus Notarchus, Proc. Malac. Sac. Lond, 22, 113-119. Toxioxa, T., & Basa, K. (1964).—Four new species and a new genus of the family Gas- tropteridae from Japan. Publs Sete Mar, Biol. Lab. 12(3), 201-229, pls. 10-13. PEARSON ISLAND EXPEDITION 19697-11. CRUSTACEA: ISOPODA BY W. F. SEED* Summary SEED, W. F., (1973) .-Pearson Island Expedition 1969.-11. Crustacea: Isopoda. Trans. R. Soc. S. Aust. 97(3), 207-212, 31 August, 1973. Eleven species of isopods, all sphaeromatids, are represented in a small collection from Pearson I. Of these species, two are too immature for specific identification, but belong to the genera Exosphaeroma and Cymodopsis. One new species, Cilicaeopsis floccosa, is described and figured. The previously-known species are: Cymodoce gaimardii, C. pubescens, C. unguiculata, Cilicaea latreillei, Cerceis acuticaudata, Haswellia anomala and H. cilicioides. PEARSON ISLAND EXPEDITION 1969;—11. CRUSTACEA; ISOPODA by W. F, SEED* Summary Seep, W. F., (1973}.—Pearson Island Expedition 1969.—11. Crustacea: Isopoda. Trans. R. Soe. §. Aust, 97(3), 207-212, 31 Angust, 1973. Eleven species of isopods, all sphaeromatids, are represented in a small calection from Pearson I. Of these species, two are too immature for specific identification, but helong to the genera Exosphacroma and Cymeodopsis. One new species, Cilicaecpsis floccosa, is described and figured. The previously-known species are: Cymodace gaimardii, C. pubescens, C. ungui- culata, Cilicaea latretilei, Cerceix aculicaudata, Huswellia anomala and H, cilicioides. Introduction This paper discusses the isopod crustaceans collected during the Pearson I. expedition of 6-13 January, 1969, sponsored jointly by the Royal Society of South Australia and the De- partment of Fisherics and Fauna Conservation of Soutb Australia. For discussion of collecting siles see Shepherd & Womersley (1971) and Watson (1973); R and § indicate rough-water and sheltered localities. All specimens Were recovered during the sorting of algal collections made by divers (8. A. Shepherd, J. EK. Watson and J. Otta- way), This may account for the immaturity of much of the material, smce larger, and pre- sumably more vigorous, animals are often ob- served to escape the net during collection (S. A, Shepherd, pers, comm.). Nine species (including one new species) are identified, and two Species are diagnosed to genus only, The keys of Hale (1929), Hansen (1905) and Hurley (1961) were used to identify the genera; most of the speciés were determined fram Hale’s (1929) keys and species descrip- tions. Syhonymies ute not necessarily com- plete. | have followed Menzies (1962; see also Menzies & Frankenberg 1966) in giving only a bricf diagnosis of the new species, supported by accurately drawn figures. Use of the name Sphaeromatidae (rather than the more commonly-used Sphueromidae) follows Schultz (1969) and Naylor (1972), and anticipates a forthcoming paper by Hurley & Jansen (pers. comm.) in which the usage ts discussed, Specimens are deposited in the isopod cal- lection of the National Museum of Victoria, Melbourne (NMV), but only the new species has been registered. Tribe FLABELLIFERA Family SPHAEROMATIDAE Group HEMIBRANCHIATAL Genus EXOSPHAEROMA Stebbing, 1900 Exosphaeroma sp- Locality: Pearson I. (Station F at 65 m), Material: One immature male, damaged (about 5 mm long). Penes are developing but appendix masculina is not yet distinct. Remarks: More than thirty species have been placed in this genus, and the specimen differs from all of them in at least one point: the uropodal exopod is W-shaped at the distal end, Description of this species must await more suitable material. Genus CYMODOCE Leach, 1813-14 Cymodoce gaimardii (Milne Edwards). Han- sen, 1905: 121, Baker, 1926: 256, pl, 42, fig. 2. Hale, 1929: 286, fig, 284. Nierstrasz, 1931: 200. Naylor, 1966: 186. fig. 2. Sphaeroma gaimardii 1840; 209, Milne Edwards, “Department of Applied Biology. Royal Melbourne Institute of Technology, 124 fa Trobe St.. Melbourne, Vic. 3000. * Other accounts of the geomorphology ard biology of the Pearson Islands are given in Volume 95, Part 3 (1971) of the Transactions, as well as lhe present Part. 208 FIGS, 1-4 Localities: Australia (Milne Edwards 1840); Vic.: Port Phillip Bay (Baker 1926, Nay- lor 1966); Tas,: (Baker 1926); S. Aust: Encounter Bay, Gulf St. Vincent (Baker 1926), New record: Peurson |. (Station F at 65 m). Material; One female (11 mm long), im- mature, With no oostegites or eggs, and the mouthparts unmodified. Remarks: The specimen agrees with the des- criptions and figures of Baker (1926) and Naylor (1964), allowing for is being a juvenile. Comparison with these figures and with specimens collected from Western Port Bay reveals variation within the species in the sharpness of truncation of the uropodal endo- pods, in the shape of the joint between telsonic and pleonic tagmata, and in the shape and degree of exposure of the anterior suture on the pleon (Figs. 1-4). Cymoaduce pubescens (Milne Edwards). Han- sen, 1905; 122. Stebbing, 1910: 104, Nierstrasz, 1931: 198. Naylor, 1966: 188, fig. 3. Sphaeroma pubescens Milne Edwards. 1840; 209, Paracilicuew (2) pibescens (Milne Ed- wards), Baker, 1926: 262, pl. 43, figs. 8-11; pl. 48, fig. 1. Hale, 1929: 290_ Locatlties: Austrilia (Milne Edwards 1840); WN,S.W.: Port Jackson, Port Stephens (Has- well 1882); Vie.; Port Phillip Bay (Nuylor 1966), Zanzibar: Wasin (Stebbing 1910), Indonesia: Sailus Besar, Paternoster 1. (Nierstrasz 1931), New record: Pearson 1, (Stution F at 65 m), Material; One mule (8 mm jong) and one female 7.5 mim long), both immature: the W. F. SEED appendix musculina of the male is not lree, the female has no oostegites Or eggs, and its mouthparts are unmodified. Remarks; Specimens agree with published des- criplions of this species. It should be noted that, although Hale (1929) has followed Baker in referring this species to Purarilicaea im the text, his key agrecs with those of Hansen (1905) and Hurley (1961), the species key- ing out to Cymedece in all three. Cymodoce unguiculata Barnard, 1914: 394, pl. 34B. Baker, 1926; 259. Hale, 1929: 285. Localities: South Africa (Barnard 1914), S, Aust.; Beachport (Baker 1926), New record: Pearson I, (Station F at 65 m). Material; Two feniles (6 and 9 mm long), both immature, without eggs or modification of the mouthparts, but with four pairs of oostegite buds in the larger specimen, Remarks: The specimens Jack the marginal fringe of setae referred to by both Hale and Barnard; the bosses on the telson are much less prominent than Barhard's figures indicute (by inference from his description, and directly from Hale's. they are the same size in adults of both sexes); and the hooked uro- podal exopad differs slightly in both specimens from Barnard’s figures, The uropodal endo- pod, however, is. slightly excavate distally, as shown in Barnard’s figure of the female, and in other Tespects the specimens agrée well with desenptions of C. unguiculaia. Genus CILICAEA Leach, 1818 Cilicaca curtispina Haswell, 1881b: 185, pl. 3, fiz. 4. Stebbing, 1905: 36, Baker, 1908; 142, pl. 4, figs. 12-17, pl. 5, figs. 1-%; 1938: pl. 6, figs, 8-9. Hale. 1929; 280, Figs. 1-4. Cymodoce yaimardii, posterior region, Fig. 1.—Female (11 tm long) from Pearson T. Fig. 2 -Female (13.5 mm long) from Port Phillin (after Naylor), Fig. 3—Male (24 mm Jong) from Western Porl. Fig. 4.—After Baker: "Prohably » young male"; locality and scale rot Indleated, CRUSTACEA; ISOPODA fiz, 280. Nierstrasz, 1931, 205. Naylor, 1966; 189, Naesa antennatliy nomen nudum, Cilicaea anrennaliy While Miers, 1884+ 310, Cilfcoaea = avitennalis = Miers, 1905: 335. Niersteasz, 1931: 205. Localities; W. Aust.: Swan River (White 1847, Miers 1884) Vic.: Port Phillip {Haswell 1881b. 1882; Naylor 1966); “very common in shallow water around [southern Australian] coasts" (Hale 1929). New record, Pearson 1. (R at 25 m). Material; Qne adult male (14 mm long). Remarks: The specimen agrees with Baker's (1908) and Hale’s (1929) descriptions, except that the uropodal cxopods are ruunded apically, rather than slightly bifid. No deserip- tion tefers to the pads of short setue lining the incurved inner surfuce of the distal part of these cxopods and of the median projection. This feature, together with the shape und atrangement of these three projections, seems to imply some definite function, such as clasp- ing the female during mating, or clasping the anterior region When the aninsal is rolled. White, i847: 105; Stebdbing, Cilicaes Jatreillei Leach, 1818: 342. Miers, 1884: 308. Stebbing, 1905: 36, pl, 8, Hiatle, 1929; 282, fiz. 282, Nierstrasz, 1931: 204. figs. 92-96, Naylor, 1966; L90, fig. 3. Neaesea latreiilei Milne Edwards, 1840: 218. Cilicvea crassicandeta Haswell, 475, pl. 17. fig. 3- Localities: There are numerous records from South Africa, Ceylon, East Indios, Australia and New Zealand [see Nierstrusz 193), Naylor 1966). New recerd:; Pearson I. (R at 20-25 m), Material; Qne specimen, apparently female and very young {6 mm), Remarks: The females of Cymodoce pubescens and Cilicaea latreitle’, both of which have bifid twopodal exopods and are otherwise very simi- lan. have caused much taxonomic confusion, The Peurson I. specimen Jacks the characteria- lic scale-sctae of Cymnoedoce pubescens, being fairly liberally covered with stiff, erect setae: it agrees well with Naylor's (1966) figure of a female of Cilicaea latrejllei, although it has not the well-defined anterior buss of the Port Phillip (and Western Port) specimens, and the posterior tip ef the uropodal exopod is forked’. 1881a; abs) These could well be juvenile features: com- purison with a series of specimens from Wes- tern Port leaves little doubt that it is a yery young female of Cilicaea Jarreillei. Jt must be noted thal the male figured by Niesstrasz, despite his statement that “Die Tiere (Figs, 92-96) stimmen put mit den Beschrei- bungen von Miers [1884], Stebbing [1905], und Barnard [1914] tiberein”, clearly belongs to another species, and what he has labelled as the female of C. latrei/le? is not a female of that species, although it could he a Votng male, Reliable figures will be found in the papers by Barnard, Naylor and Stebbing; they agree with all Victorian specimens available. Genus CILICAEOPSIS Hansen, 1905 Hansen established this genus by designating Cilleaca granulata Whitelegge (1902) as the type, and his key to genera shows the diagnos- tic characters to be; “Abdominal notch semi- circular, without any vestige of mesial lobe. ndp, of urp. rudimentary in the tale", This seems to have been broudly interpreted as to both the semicircular nature of the abdom- inal notch and the rudimentary nature of the endopod. Some of the species included in this YeNUsS appear to necessitate a new generic diag- nosis, but it will be best if modification of the agnosis is left until this and the several closely-related genera are reviewed. Taking a broad view of the meaning of semicircular, as Baker (1926) has done, the new species described below conforms with Hansen's diagnosis, Cilicaeopsis flaccesa n,sp. Locality: Pearson 1. (R at 25 ma: “From algae on horizontal face”). Material: One specimen, the holotype male (median Jength 12,5 mm, total Jength 16 mm, width 6.1 min), wpparently adult, § A, Shepherd, 10.i,1989 (NMY, J-249). FIGS. 5-11 Diagnosis: Citicgeaopsis: with slender, curved tropodal exopods beuring a Furry tuft of setae on the median aspect of the distal end. Simi- lur selae cover the dorsal surface of the endo- pods and of the pleotelson below and behind the two Jarge tuberculate bosses; surface else- where glubrous. Appendix musculina Jong, with a curved narrow tip extending well beyond the setae of the second pleopod; inner edge of the endopod grooved behind ta accom- miodate the upper part of the appendix. Penes long, tapering to a point. taterally compressed and kinked backward near the end, Abdominal W. F. SEED Imm FIGS, 5,6,7 5mm FIGS. B. 9. 10, 11 Figs. 5-11. Cilicaeapsis floccosa. All figures from the holotype male. Fig. 5—Left maxillipede, Fig. 6. —Left penis, from the right side, Fig. 7—Left second pleopod and appendix masculina. Fig. 8.—Head, ventral view. Fig. 9. Whole animal, dorsal view. Fig. 10.—Posterior region, from ihe left side. Fig. 11.—Pleotelson and uropods, ventral vicw. CRUSTACEA: ISOPODA notch wide and shallow, not visible from above. Epistome pointed, much shorter than broad. Genus CYMODOPSIS Baker, 1926 Cymodopsis sp. Lacalitys Pearson T, (R at 25 m, from algae on horizontal face). Material; One immature male (8 mm Jong), with very rudimentary penes and appendix masculina not yet appyrent- Remarks: The specimen superficially resembles Baker's (1926) figure of Cymodopsis crassa in general form and in having two large coni- ¢al projections on the pleotelson. In lateral yiew these are seen to be slightly undercut below. forming a postcro-dorsal point on cach, whereas the corresponding part of Cy. crassa appears, in Baker's figure, to be smoothly rounded and to run down to the telson as a straight ftidge. Two other conspictious dif- ferences are that the epistome is very much shorter than broad (and different from that of uny described species), and that the uropodal exoped is relatively Jarge, plate-like, and rejches to the end of the endopod in the ¢losed position, It seems clear that this is a new species, but no sauistactory description can he given in the absence of an adult male. Group BURRANCHIATAE Genus CERCEIS Milne Edwards, 1840 Cerceis aculicaudata (Haswell). Hansen, 1905: 127, Hale, 1929; 300. Nierstrasz, 1931: 214, Sphaerama (9?) acuticaudata Haswell, T8R1b; 197, pl 3, Fig. 9, Localities: Vic. Griffith's Point, Port Phillip (Haswell L&K1b); “This is a common apectes” (Hale 1929), New record; Pearson I. (R at 25 m, from algae on horizontal face. R at 20-25 m). Material: Three females (8.5-9.3 mm long), all immature and Without ooslegites or eggs. Remarks: Specimens agree with descriptions and figures of Cercels aeuticaydata except that they lack the spines on the Urupods and the spine on the pleotelson Is represented only by 1 a smooth median boss. Comparison with a series of specimens from Western Port shows that the growth of these spines is both allo- metric and variuble. Genus HASWELLIA Miers, 1884 Haswellia anomala (Haswell). Baker, (026: 273, pl, 48, figs, 8-9. Naylor, 1966; 192 Sphacroma (2?) anormnala Haswell, 188ba. 473, pl. 16, fig, 4, Zuzara emarginata Haswell, 1881 b: 188, pl. 3. fig. 5, Taswellia emarginata (Haswell), Hansen 1905: 127. Hale, 1929: 304. fig. 304. Localities: N_S.W.: Port Jackson (Haswell 188la): Vie.; Western Port (Haswell L881b), Port Phillip (Naylor 1966); 8. Aus! St. Vincent Gulf (Hale 1929). New record: Pearson I. (R at 25 m). Material; Seven females (5.88.6 mm long), all immature and without eges, oostegites, or modification of the mouthparts. Remarks: The females of this. species are very similar to those of Cerceis trispinosa. The uro- poual exopods provide a convenient diagnostic feature; in C. sispinasa females they are longer than the endopods, while in A. anemate they are both slightly shorter than the endo- pods, and conspicuously toothed on the distal edge. Comparison with a series of A. anomala from Western Port confirms the identity of the Pearson I. specimeus. The largest of them have the hind. margin of the seventh thoracic tergite produced in the centre (although not as fay as in Haswell's figure of Sphacroma (7?) ana- mala), a feature which supports Naylor's view that S. (7?) anomala was the fernale of this species and hence also supports his adoption of the specific epithet anomala. Haywellia cilicioides Baker, 1908: 158, pl. 10, figs, (2-23. Hale, 1929: 304, fig. 305. Localities: S, Aust; St. Vincent Gulf (Baker 1908, Hale 1929), New recerd: Pearson T- (S at 30m). Marerial: One adult male ( 9 mm long), Remarks; The specimen agrecs with Baker's (1908) and Hale's (1929) descriptions and figures, except for slight differences in the shape of the uropodal endopods, and in the shape of the process of the Jast thoracic seg- ment when viewed from above. 21> Ww, F. SEED Acknowledgements Tam grateful to the Director of the Nationul Muscum of Yictoria for facilities for this study, und to the Science and Industry Endow- ment Fund (C,S.1R,.0.) for a grant-in-aid. Mrs. J. BE. Watson und Mr, A. Neboiss read the draft manuscript and made a number of helpful coniments. References Bagel, W. H, (1908), -Notes on some species of the isopod family Sphaeromidae from the South Ausiralian coast, Trans. R. Soc. 8. Aust, 32, 138-162, pls. 3-10. Baker, W. H, (1926).—Speciés of the isopod family Sphaeromidae from eastern, southern and western coasts of Australia. Trans. R, Sac. S- Aust. 50, 247-279, pls. 38-53. Bakrr, W. IT. (1928) —Australtan species of the isopod family Sphaeromidae (continued). Trans. R, Sov, §. Ads. 52, 49-6], pls. 1-6, Barnarn, K. H. (19'4)—tConirihutions to the Crustacean Fauna of South Affica, 3.—Addi- tions. to the Marine Isopoda. with Notes on some previously incompletely known Species. Ann, S. Afr. Mus. 10, 32Sa—358a, 359-442. pls, 27-38. Hare. H. M, (1929).—"The Crustaceans of South Australia”. Part 2, (Government Printer: Adeluide: ) Hansen, H. J. (1905)—On. the Propagation, Sirugture and Classification of the Family Sphieromidae. Q. J] miarose, Sei, 49, 1s. (193), 69-135, pl, 7, HASwWeit, W. A. (1881a)—On some new Ans- tralian Marine Jsopoda. Part I. Prac. Lite Soe, NSW, 5, 470-481, pls. 16-19, Haswrib, W. A. C€§88Ib)—Gn some new Aus- tralian Marine Jsopoda, Part Ul. Prac. Linn. Sac, NSW. 6 181-196. pls, 3-4. Hasweut. W, A. (1882).—"Catalogre of the Ans- tralian Stalke and Sessile-evyea Crustacea”. (Australian Museum: Sydney.) Hurry, D, E. (1961).—A Checklist and Key to the Crustacea Isopoda of New Zealand and the Subantarctic tslands. Trans. R_ Soe: N.Z. (Zool.) 1(20), 259-292. Teach. W, LE. (t&13-14).—Crustacenlogy. Jn “Rdinhurgh REncyclopyedia* 7. (Blackwood ve. al: Edinburgh.) Leach W. EB. (1818).—Crustacés. In “Diction- naire des Sciences Naturelles” 12. (Levrault; Paris.) Munvins, R. J. (1962).—The Zoogeogranhy. Ecology and Systematics of the Chilean Murine Tsopods. Acra Univ. lind., NvF. Ava. 1, S7(11), 3-162. Menzies, R. J... & PRANKENBERG. D. (1966).— “Handhook on the Common Marine Isopod Crustacea of Georgia.” (University of Geor- pia Press: Athens.) Miers, E, J. (1/884). -Crustaces. Jn “Report on the Zoological Collections made in the Tndo-+ Pacific Ocean during the voyage of H.M,S, ‘AlerU, 1861-2," pp. 178-322. pls. {&-34. (British Muséum (N. H,); London.) MILNE Enwaros. H, (1840).—‘Histoire Natnrelle des Crustacés” 3. (Libraire Encyclopedique de Boret: Paris.) NayLor, BE. (1966).—Port Phillip Survey 1957- 1963. Isopoda, Afem. natn. Mus. View, 27, 183-198, 377-384, charts 1-2. Nayior, K. (1972).—"British Marine Isopoda”, (Linnean Society of London & Academic Press: London.) Nierstaasz H. F. (1931).—Die Isopoden der Sibugu-Expedition, HI, Tsopoda Genuina. IT. Flabellifera, Siboga Fxped. 32c. 123-233, 2 pls, Scnuurz, G. A. (1969)—“How to Know the Marine Isopod Crustaceans” (Brown: Iowa.) SHEPHERD, 8, A. & Womerscry, H. B.'S.. (1971). —Peurson Island Expedition 1969-7. The Sub-tidal Ecology of Benthic Algae. Trany. R. Soe. S. Aust. 95, 155=167. StrrnninG, T. RR, (1900).—-On some Crustace- wns from the Falkland Islands collected hy Mr. Rupert Vallentin. Pree. Zool, Sec. Lond, 1900, 517-568, pls. 36-39. STepuina, T. R. R. (1905).—Report on the Tso- poda collected by Professor Herdman at Ceylon, in 1902. Rept. Ceylan Pearl Oyster Fishevtes, Part 4, Supplementary Reports. No, 23, (Royal Society: London.) Sreening, To R. R. ¢€1910).—Isopoda from the Indian Ocean and Bittish Basi Africa. The Perey Sladen Trust Expedition. Indian Occaa 1905, Vol. WH, No. VI. Trans. Linn. Soe. Lond, Zool. 14 (1), 83-122, pls. 5-11. Watson, J. E. (1973)—Pearson Island Bxpedi- tion 1969.9. Hydroids. Trans, R, Sac. 8. Aust, 97 (3), 153-200, Wuitr, A. (1847).—"List of the specimens of Crustacea in the collection of the British Museum. (British Musenm London.) WHITELEGGE. T. (1902).—"Scientific Results of the Trawling Expédition of H.M.CS. ‘Thetis’. Crustacea Part TI, Tsopoda Part Il." (Australian Museum, Sydney.) STRATIGRAPHY, STRUCTURE AND METAMORPHISM OF THE KANMANTOO GROUP (CAMBRIAN) IN ITS TYPE SECTION EAST OF TUNKALILLA BEACH, SOUTH AUSTRALIA BY B, DAILY* AND A, R, MILNES} Summary DAILY, B., & MILNES, A. R. (1973). -Stratigraphy, structure and metamorphism of the Kanmantoo Group (Cambrian) in its type section east of Tunkalilla Beach, South Australia. Trans. R. Soc. S. Aust. 97(3), 213-242, 31 August, 1973. An apparently conformable sequence of metaclastics forming the upper part of the type Kanmantoo Group (Cambrian) has been mapped along 50 km of coastline between Tunkalilla Beach and Middleton Beach. Sporadically occurring black carbonaceous and sulphide-rich phyllites are confined to and characterise the Brown Hill Sub-group. Associated immature "flysch-like"” metasediments were deposited very rapidly in an actively subsiding basin by currents flowing mainly from the NW. Numerous pebble beds, similar to those in the underlying Inman Hill Sub-group, reflect the continuity of the Kangarooian Movements. The cross-bedded Middleton Sandstone at the top of the overlying Wattaberri Sub-group was deposited by currents directed mainly towards the east. STRATIGRAPHY, STRUCTURE AND METAMORPHISM OF THE KANMANTOO GROUP (CAMBRIAN) IN ITS TYPE SECTION EAST OF TUNKALILLA BEACH, SOUTH AUSTRALIA by B. Daity* and A. R. MILNES} Summary Datry, B., & Mines, A, R. (1973).—Stratigraphy, structure and metamorphism of the Kan- mantoo Group (Cambrian) in its iype section east of Tunkalilla Beach, South Australia. Trans. R, Soc. 8. Aust. 97(3), 213-242, 31 August, 1973. An apparently conformable. sequence of metaclastics forming the upper part of the type Kanmantoo Group (Cambrian) has been mapped alone 450 km of coastline between Tunka- lila Beach and Middleton Beach. Sporadically occurring black carbonaccous and sulphide-rich phyijlites are confined to and characterise the Brown Hill Sub-group. Associated immature “fiysch-like” mictasedimenty were deposited very rapidly in on actively subsiding basin by currents flowing mainly from the NW. Numerous pebble beds, similar ta those in the underlying Inman Hill Sub-group, reflect the continuity of the Kangarooian Movernents, The cross-bedded Middleton Sandstone at the top of the overlymg Wattaberri Sub-group was deposited by currents directed mainly towards the east. Kanmantoo Group rocks younger than the Middlcton Sandstone are unknown in the Mt. Lofty Ranges, Because the formation is intruded by the Encounter Bay Granites, a thick cover must have been present at the time of intrusion and metamiurphism. Warm casts were the only fossils located in the study area und are suggestive of a marine environment of deposition. The sequence mapped forms the eastern limb of a regional anticline overturned towards the NW. Two phases of folding are recognised. F; folds plunge shallowly towards the SSW er NE. Eastwards from ihe core of the highly appressed and asymmetrical regional anti- cline, F; folds in metasandstones become progressively more open, symmetrical and upright. Mesoscale Fo folds with E. to SH plunges are confined to the eastern patt of the type section. A weak crenulation of S$; is observable near Coolawang Creek, and becomes progressively stronger towards the east. The Encounter Bay Granites were intruded and had crystallised prior to the main phase of FP, deformation because thin granite sheets, concordant with bedding, developed the §; and S» schistosities during the folding episodes, Stability fields for the observed metamorphic mineral assemblages show that the meta- morphism of the Kanmantoo Group was effected at moderate temperatures (below 540°C) and Tow pressurcs (below 3 kb). This is indicated also by the well preserved sedimentary sftuctures found throughout this sequence of undalusite-staurolite prade rocks, Cordierite, restricted to the proximity of the granite, records the highest grade of metamorphism within the type section. Petrographic evidence suggesis that cordierite crystallised during the pre- to early syn-Fy phase, a conclusion in harmony with the suggested pre-tectonic emplacement of the Encounter Bay Granites. Petrographic evidence indicates that most of the sndalusite formed during the late syn-F; phase of metamorphic crystallisation. In the post-F, and pre-F. static phase of meftamarphic crystallisation, some andalusite, garnet, hornblende, *Centre for Precambrian Research, Department of Geology and Mineralogy, University of Adelaide, Adelaide, S, Aust. 3001, + GS.1R.0. Division of Soils, Glen Osmond, 5. Aust, 5064, Formerly, Department of Geology and Mineralogy, University of Adclaide. 214 B. DAILY and A. R. MILNES scapolite and chlorite grew across the S; schistosily, The 8. crenulaiion cleavage, where developed, deformed porphyroblasts of this age. Albitisation postdates the Sw schistosity. A peculiar “striped” layering. post-S; and pre-S. in age, occurs within the Petrel Cove Formation west of Rosetta Head and resulted from alteration adjacent te tensional fractures. Two distinc! groups of basic dykes. post S; and pre-S» in age. cut Kanmantoo Group metasediments. Introduction A previous paper (Daily & Milnes 1971a) discussed the geology of the Jowcr part of the ‘ype sezlion of the Kanmantoa Group (Sprigg & Campana 1953) as found in the coastal clitls of Fleurieu Peninsula between Campbell Creek and the western end of Tunkalilla Beach (Figs. 1 & 2). The present paper gives the results of our investigations of the geology for the re+ mainder of the type section east to Rosetta Head near Victor Harbor. In addition, we have extended our averse to include stratigraphi- cally younger metasediments to the NE in the Port Elliot and Middleton areas. The stratigraphic succession und geological structure over this 50 km of coustline (Figs, 3 & 4). differ significantly from that shown on the map given by Madigan (1925), on the Jervis (Campana & Wilson 1954) and Encoun- ter (Crawford & Thomson 1959) 1;63,360 Carrickelnaa Hes Normanwilie 2 hy Le] 555 VR Canneshaw Afwadle Arver KANGAROO ISLAND Fig. LL Figs, 2-4, map sheets, on the BARKER 1:250,000 map sheet (Thomson & Horwitz 1962) and in the ‘Handbook of South Australian Geology’ (Thomson 7m Parkin 1969). In essence we have found that progressively younger formations occur to the east despite the advent of folds which repeat parts of the sequence. These: folds dre inclined to upright and plunge at relatively low angles towards the SSW. hut as shown on the maps, some exceptions in plunge direction do occur, particularly in connection with parts of the Wattaberri Sub-group. Our main aims in studying the geology of the type Kanmantoo Group have been to te- assess. US stratigraphy and age limits and to try and determine the relative time of emplace- ment of the Encounter Bay Granites in con- trast to the isotopic ages obtained by Dasch ef al, (197), In the presumed absence of diag- nostic foszils within the type section, we have a a = n a) uy io Houghton = > ex & ADELAIDE a ao e uneaa Naifne e Brukungea \ « Kanmantoo I Call +45, oc Sa, 2 Callington tr Barber C4 K Selick Hil A eo Wit Cornpass cut Hil ee a) got alaman HiRes « ue Hindmarsh Valley co Ass, “SA DUDLEY’ FEMINSLULA, ~G Willoughby © Hart 20 K'LOMETRES bent el ee I Locality mup of geographic features. exclusive of those shown on the geological maps in GEOLOGY OF TYPE SECTION, KANMANTO0 GROUP (CAMBRIAN) ON been forced to define the relative age of this emplacement i tetms of the structural and metamorphic history of the Kanmantoo Group, Fortunately, sufficient rock samples were col- lected and enough structural observations were recorded during our traverse jo enable us to siggest the emplacement of the granites prior to the culmination of the first phase of defor- mation. We have not attempted a rigorous analysis of the structure and metamorphism of the Kan- manloo Group it tly Lype section, and further work to this end is warranted, However, oite of us (Milnes unpub.) has discussed “The En- counter Bay Granites and their enviranment’ in greece delail in a Ph.D, thesis, aubmitted to the University of Adelaide. Stratigraphy In presenting the geology of the upper part of the Kanmantoo Group we have revised the stratigraphic terminology previously applied in the type section (Daily & Milnes 19729). This scheme is given in Table {, As explained in the 1972 pauper, we have discarded the term TABLE. | Stratigraphic scheme for the Kanmantoa Group tn ity mpe section between Campbell Creek anil Rosetta Head. The table also includes strotigra- phicaily younger metasediments ia the Port Eltiot- Middteion arva and alsa shows the relationship af the Kanmanioo Group ta-elder rocks (Precam- brian and Cambilan) on Fleurieu Peninsula, The regional unconformity between Precambrian and Cambrian strata represents roughly the stratigra- phie interval from the ABC Quartzite of the Flin- ders Ranges to the hase of the iransgressive Carm- brian sleposits- Middiciwn Sandstone Waraherel Sub-group Petre! Core Formation Belauhidder Farmaion Town Flu Snb-eroun Tunkalilla Formation Tapanaiiya Farmition KWanmanion Grain Talisker Cale-siltsnone Cambrian Sysivii\ Tamz2c Hill Sub-aroun Wacksiairs Passage Formation Cavitkalinga Alvad Foviation Campana Creek Mumher Biiwhnte Crock Sillfione Member Madigan Inlet Meniber Normunyvilte Group Remonal Unheonlinity Marinn Group (Laie Preegnibrignl Brukunga Formation but have retained the veo. graphic terms Inman Hill and Brown Hill to qualify sub-proup names, This procedyre re- tains the position of the boundary between the Taman Hill Formation and Brown Hill Beits as desigaated initially by Forbes (1957), More- over, the base of the Brown Hill Sub-group, which is easily recognised, docs not correspond to the base of the Nairne Pyrite Member at the hase of the type Brukunga Formation. The base of the Brown Hill Sub-group is estimated In be 3000-4000 m above that position in the Nairse region where the Brukunga Fornsation was originally detined, The following abbreviated gocount has been made from our field notes of the coastal sec- tions and environs east of Tunkalillu Beach A. INMAN HILe Sup-croup (new rank) The Inman Hill Sub-group (Table 1) con- tains the Backsteirs Passage Formation, Talisker Crilc-siltstone and Tupanappa Forma- tion, All three formations occur in superposi- tion in their type sections. In addition, we have now located them on Dudley Peninsula, Kan- guroo 1. (Daily & Milnes 1971b) where they appear to be of identical facies. However, we have had difficulties in identifying the Tapa- nappa Formation in the northern sections of Fleurieu Peninsula, although Tapanippa For- mation of comparable lithology to that ex- posed in the type section is well exposed along the Mount Barker Creek, near Callington, fur- ther to the north. So far we have not mapped any intettongucing relationships between typical Tapanappa Formation and other formations, nor have we recognised fault relationships that Might account for jis apparent absence in some sections, Nevertheless, we believe that such possibilities do occur and we have recently undertaken investigations in key areas to solve these problems, Tapanappa Fermation Detailed observations on the lower part of the Kanmantoo Group (Daily & Milnes 19714), ditt not extend beyond the western end of Tunkalilla Beach where the modem coastal clifis abut upon the beach, However. there ix an arcuate line of old coustal cliffs behind an alluvial bench backing that beach which per- Mitted collection of data for the uppermost part of the Tapanappa Forniatiun, despite the rela- tively poor outereps in comparison with those in the thodern coastal cliffline, The sequence Cunsisty of dark coloured, thick-bedded to laminated, generally fine- to coarse-grained metusandstoncs, although near the top of the Th formation ver¥ fine-grained metasandstones predominate. The individual metasundstone beds, rarely more than 1 nm thick, are split by povrly eutcropping and {frequently Juminated octasiltslones and phyllite interbeds which are penerully much thinner than (he metasand- stones, These pelites range down tu partings of i few millimetres. Poorly outcropping intervals. many in excess of 10 m Stratgeaphic thickness, are presumed metasiitstones or phyllite beds. Bunds und tods ol cale-silicates occur spora- divally in the metasandstones and even in some of the finer grained lithologies. Porphyroblasts oft chiurite. muscovite and bielite dre common in the finer grained lithulogies, especially the phyllites, ws well as some of the metasandstone bands. Onternps of small-scale conglomerates uceur ws thin discontinuous bands in same uf the coarser grained metasandstones but their presence in the sequence was generally inult- cated by float rather dha outcrop, B, Brown Hit. Sup-croue (new rank) The base of the Brown Hill Sub-group and the Tunkalill Pormatioi is marked by a sequence of dark blue to black laminated phyl- lites ybout 15 m thick (not 10 m as in Daily & Milnes 197 1a, p, 207), and outcrops on a small suddle hehind the beach about 2.5 km west of Tunk Head. The Tunkalilla Formation to- gether with the overlying Balquhidder Forma- tion constitute the Brown Hill Sub-group. ‘The lithologies within the sub-group ure not unlike those found in the Tapanappa Formation and indeed jt is impossible to: assign limited se- quences to either unless the dark blue-black carbonaccous and sulphide-rich phyllites cha- racteristic of the Brown Hill Sub-group. are located within them. Fortunately, dark coloured phyllites of this type are unknown to us guiside the sub-group within the type ares. Geopraphicolly, they ure quite extensive as they are known from Middle River (upstream from the dam site} on Kanyguroo L, liorth to at least ihe Callington areca in the eastern Mt. Lofty Ranges. Tunkalilla Formation (new name} Vhe dark coloured laminated phyllites rark- ing the base of this formation conformably overlie the Tupanappa Formation metiasédi- ments, When weathered, the phyllites are characteristically stained yellow and brown by jarosite ond guethite due to the oxidation of iron sulphides within the Tock, Stratigraphically above this basal unit are about 30 m of poorly cutcropping dark coloured medium- to course- grained mactusandistones with interbedded meta- B. DAILY and A. R, MILNES siltslunes und phyllites. Succeeding this there is a khaki to mid-grey coloured phyllite about 30 m thick overlain by a 200 m thick sequence of alternating Lo m thick bands of fine- to mediuin-zrained melasandstones und Khakl to mid-grey coloured phyllites. ‘These are in turn overlain by a thick sequence (ahoul 150) a} of predominantly well laminated metusiltstones (Fig. 8) andl phyllites with minor metusand- stone interbeds cut-and-fill into the finer clas- tics, This interval vecupies: low ground and outcrops poorly. Elongate to ovoid porphyro- blasts wf micas iunlchlorite are Cummon in the metasiltstones. Several small quartz-feldspar- chlorite-muscovile pegmultiluy oocur in silky phyllites near the mouth of Tunkalilla Creck. A well developed crenulutvon is present in the phyllites immediatcly adjacent to these ‘sweat’ Peymaliles, but this is local and has nov been vbserved elsewhere. The topmost part of the Formation is a well laminated phyillite-metasilistone to fine-grained metasandstone sequence capped by sc least 3 m of blue-black luminsted carbanuccous phyllites in which the alteration of sulphides. has. pra- duced jurosite and poethite. Cubie shaped voids after pyrite are readily upparent in the wea- thered phyllites. The best outerops can be in- spected high up on a mainly soil-covered west facing cliff about 100 m east Of Tunkalilla Creck, after which the formation is named. The position of the upper boundary of the Tunkalilla Formation is plotted on ihe geo- Jogical map (Fig. 3). In the first creek west of Cullawonga Creek. a & m thick band of black sulphide-rich finely laminated phyllites stained With jarosile and geethite marks the top of the formation, It is underlain by about 3 m uf metasinistone., Below the melasandstune there is a much thicker poorly outcropping bund of blue-black carbonaceous and — sulphide-rich phyllites which, providing there are no struc- (ural complicahions, may haye a thickness of 30 m. Paler coloured phyllites and metasilt- stones occur below this. We may have missed this approximately 30 m band of black phyllite in the type section due lo thick soil gover at this stratigraphic level. In craverses east of Cul- lawonga Creek however, we Jocated only the upper of the tWo bands and therefore i is more Jikely that this thick band is a local develop- ment. The only fossils found within the formation dre abundant worm casts in outcrops of sand- blasted metasandstenes at the back of Bolla- parudd’a Keach, adjacent ba the westeen hank GEOLOGY DF TYPE SECTION, KANMANTOAO GROUP (CAMBRIAN) ZL of that creek, The worm easts (Figs. 9 & 14)) are exceptionally well-preserved despite the tec tonisia and metamorphism. ‘They are weathered out in full relicE in an ourgrop about 8 m tong and their tubular and sinuous nature can be seen to pericction, particularly in sections nor- mal to the bedding. The bioturhared interval, Which is obour 20 cm thick, forms the topmost bed in a large scour-channel (Fig. 14). The lower parts of the channel comtain shale-chip conglomerates in which the now phyilite frag- mcals are scattered in a metasandstone matox. Thus the Tunkolilla Formation in its type section ut Tynkalilla Creck is a sequence (at levtst 250 mM thick) of muinly fine-grained clas- tics whose base and top are marked by bluc- black carbonaceous and sulphide-bearing Jami- nated phyllites of « characteristic appearance, In the region to the narth of Hindmarsh Valley mapped tty Forbes (1957), 4 seemingly iden- tical sequence can be found on Mr, J. Grevn's property just over | km SE of *Panybuly” homestead (see Milang 1:43,000 map sheet, Horwitz, & Thomson 1960, fo) the geographic position of “Pambula''), Balquhidder Formation (new name) This formation is named afler the property known as “Balquhidder (see Fig. 3), Its lype section spans the coastline from a puint approximately 2 km west of Tunk Head ease te a point about 0.7 km west of King Poine, where the much finer grained metaclastics marking the base of the overlying Wattaberri Sub-group are first encountered. There is con- tinlOus Outcrop over this upproximately 30 km of coastline except for the two stretches occu- pied by Parsons Beach and Waitpinga Beach However, the sequence is repeated by folding across these two intervals so that our observa- tions have covered most, if not all, stratigraphic Jevels within the formation. The oldest part of the formation occurs within a southerly-phing- ing broad synclinal structure whose axis les immediately west of Tunk Heath A sequence of medium- to coarse-grained metasandstones with metasiltstone interbeds vecurs at the base of the formation, These are conformable with the underlying Tunkalilla Formation, About 300 m straligraphically above the base of the formation and west of Tunk Head. there is a 10 m thick sequence of black carbonaceous and sulphide-rich phyllites, Exposures are normally covered by sand on the coast between this outcrop and the base of the formation, but a seyvenge can be examined ine land in the ancient coastal cliffs. The bulk of ~t the rocks are thick-bedded, medium- to coarse- gramed metasandstones with thin interbeds of metasiltstones or phyllites, However, there ure intervals Where the metusilistones (up to 3 im thick) are the dominant lithology and are inter- bedded with metasandstones up jo | m thick. Some thin blue-black carbonaceous and pyritic phyllites were also nuted, Porphyroblasts of chlorite and micas occur in many phyllite inter- beds as well as in some fine-grained metasand- stones. The basal part of the formation is best seen it coustal exposures, for example in a traverse from Tunk Head east to Bollaparuilda Beach. In these superior outerops the sequence has a different character, For instance, many of the seemingly massive metasandstones are well laminated and crass-bedding becomes nore apparent. Other notuble features include phyl- lite-chip conglomerates (up ta 0,5 m thick) which are associated with coarse-grained to zranule-rich metasandstones in cut-and-fill structures, load casts and associated flame siructures, and beds with climbing ripples (Figs. 11-13). Cale-silicute rods and hands are also apparent (Piys. 15 & 14), Above the lowest blue-black carboouceots and sulphide-rich phyllites within the Balyu- hidder Formation on both limhs of the Tunk Head synclinc, medium- ta yery coarse-grained missive anu laminated mectasandstones are do- minant (Figs 17-19). The beds are variable in thicknesa and generally less than | m_ thick, ancl where this is the case the sequence has somewhar flagey appearance (Fig. 20). How- ever, there are intervals where metasandstones are Up to 3m thick. Nevertheless, the thickest bed recorded was. a 15 m thick band of medium- to coarse-grained metasandstene occurring adjacent to a thin black carbonaceous and sulphide-rich phyllite within the uppermost beds of the syncline, Thin bands and lenses of small-scale pebble conglomerates and phyllite chip bands occur sporadically through the sequence and are generally associated with the coarser sand mteryals. Small-scale sedimentary structures are most frequently found in the metasillstones and laminated phyllitic intervals (Fig 21). Cale-silicate bands ad rods are again common. The black ¢arbonaceous snd sulphide-rich phyllites are best seen on the eastern limb of the syncline just vast of Tunk Head with the highest band visible in a gulch immediately west of the tazor-edged ridge constituting that head, Sulphides concenrewied into cross-culting 218 fh. DAILY and A, R, MILNES veins within this wnit at thiy focality were pro- byhly remobilized at or subsequent to the ume of metamorphism (Vig. 22). Between Calluwonga and Bollaparudda Beuches, the hagal part of the formatiun ts simi- lar tw that described above, except that small- scule Conglumetutes are present in some of the cut-and-fill structures within thick mietasand- stones. Phyllite-chip conglomerates are again conimun ussaciales. On the point 0.4 km SE of Bollaparudda Beach, there are massive and well-bedded course-grained metasandstanes, 15 em to 7 om in thickness. ulternating with phyllite and meta- siltstoie interheds. Many sands are bioturbated. Higher in the sequence pebble bands (includ- ing gaciss pebbles up to S cm across) and lenses of small-scale conglomerates occur with- in laminated medium- to coarse-grained: meta- sandswnes (Fig, 231. Phyllite-chip congle- merutes ure aussaciuted with these canglomer- ates venerally near the bottom of chunnoels. Additional pebble bands in very massive lonk- ing mielasanustones occur higher im the 3e- quence. At first sight some thick bands appear lo be structureless graded units with pebbles near the base and. with grain size fining up- wards, However, in all cases the sands were found in detail to be well bedded (Fig. 24). The high incidence of conglomerates in the lower purt of the formation cast of Bolla- purudda Beach contrasts with their relative paucity further west. The conglomerates arc comparable with those found in the Tapanappa Formation. Similar conglomerates in’ rocks which we regard ay being well down in the Balquhidder Formatiun occur in the Cut Hill roud-eutting: on the Mt. Compuss-Victor Har- bor toad. ‘Therefore, it seems thal conglome- rates in this general stratigraphic position may be a widespread feature of the formation, thus refiecting the continuity of the Kangarooian Movements (Duily & Forbes 1969: Daily & Milnes 1971a) which were partly responsible tor the deposition of the Kanmantog Group. A byck carbonaceous and sulphide-rich phyllite occurs near the cape about 1 km cist of Bollaparudda Beach and is overlain by a seyuience of anrinated to poorly-bedded meti- sandstone beds {up to | om thick) with thin phyllite and metasiltsione interbeds. From here to the mouth of Coolawong Creck the strike is almost parallel to the coast. A 3 m thick band of black carbonaccous and sulphide-rich phyl- fite overlain by thick poorly-hedded metasand- stones and thin {nterbeds ol metasiltstanes and khaki-coloured phylites occurs at the moulll of Coolawany Creck This may be the same sel. phide band 4s seen on the cape alluded to above. Between Covlywang Creek and Pitsons Beach, a number of fuld hinges and minar sults were loculed within the successiun. Mak- ing due allawance for these, the sequence 's seen to consist mainly of orassive Lo yell- laminated metasandstones in the lower part of the succession. Many of the channels cut within the sands are filled with coulse-graincd to granule-sized claslics including, Jenses ol sill pebbles, Nodules aiid irregular shaped bands of chle-silicate lithology are developed in some parts of the sequence. About T kim east of Coolawang Creck, porphyroblusts of scapolite occur in slumped and laminated metasand- stones and phyllites, [a some of the metasill- stones hoth scupolite and garnet muy be found In ihe sume arca pexmatites and feldspathived vones are common and are offen associated with tensional Features developed in) massive metasandstone bedy split by thin phyllites ( Figs. 35 & 26). A litle higher in the sequence some of the mussive metagandstones (1-2 m thick sod split by phyllites up to 1 m thick) are biolurhuted towards their tops. A weak créenu- lation cleavage, noticed for the first lime in our travetse, becomes much more apparent as one moves to the east. und provides evidence for a second phase of folding, The first-generation folds are open and asymmetric with steep westerly-dipping unticlinal limbs in contrast to the inclined folds further west possessing over- turned easterly-dipping anticlinal limbs, The opening up of the fold hinges might he con- sidered a function of distance wway from the crystalline basement at the time of folding. lhe remainder of the sequence vast to Par- sons Beach is made up of flaggy laminated metusandstones, generally less. than 1 m thick, with interbedded thin laminuled and sumetimes rippled metasiltsiones (Fig. 27) and ercnulated phyllites up fo 0,6 m thick. Some of the sanils are biowrbated und some contain cule-silicate nodules, A feature of this pant of the formation is the Fashion in which the cleavage has des- troyed or vastly modilied the fine sedimentary structures within the top (and bottom) few centimetres of the sandier beds. Bedding sur- faces, the stoss side but absent on the lee side of mego-ripples. A band of ceenulated andalusite schist was found about 20 m east Trom the commencement of oimcrop. Above this and below a 2 mihick black carhonaceous anid sul- phide-rich phvilife is a thick metasandstonc: 219 Stratigraphically higher ts a very thick sequence of metasandstones (beds generally Jess than 2 m thick) which alternate with phyllites or Thetysiltstones. ang an ocexsional much thicker Metusandstone interval (Fig. 31), Two addi- tioagl Black carbonaceous and sulphide-bearing phyllites and two bands of andalusile schists were located in this latter sequence, Strati- stiuphically above and perhaps 300 m NE of Newland Ueud, another prominent blue-black curbonuceous and sulphide-rich phyllite is inter bedded in the flaggy sequence (Fig. 32). This can be readily followed for about J km before it strikes jwland and is Jost from view. IL is overlain by coarse metasandstones containing weak developments of small-scale couglomer- ales in an otherwise flaggy sequence, From this point onwards to within about 2 km west of King Point (Fig. 32), the strike of the beds parallels or is slightly oblique to the precipitous coastline, parts of which ure totally inacces- sible. Consequently, our traverse was made mainly along the tep of the coustal cliffs. An- other slightly younger blue-black phyilite occurs 2.4 km NE of Newland Hew and below well-bedded, coarse-grained. impure metasand- stones. split hy thin phyllites. Aboul 1,5 kin WSW of King Beach a 2m thick band of a comparable hlie-hlack sul- phide-rich phyllite uceurs above a regnlarty bedded medium- to coarse-zrained metasand- stone with thick laminated phyllite partings, Tt is either stratigtaphically above or possibly on the same horizon as the blue-black phyllite mentioned shove. Towards King Point lami- nated metasandstones, often with cut-and-fill structures, occur in beds varying from abeut 19 cm to § m in thickness. Banded metsilt- stones aud finely crenulated phyllites (maxi- mum thickness about 2 m1) occur as interberls and may contain porphyroblasis of mica or more rarely andalusite. The uppermost part of the formation is marked hy a sequence of relatively fiagay metasandstones and tactasiltstumes, in which there are a number of interbeds of knotted undulusite schists, Cordicrite parphyrnblasts andl =o quartz-tich uyyregites co-exist. with undulusite in some of the schists (Fra, 347, ‘the cordicrite porptyroblasts and quact¢-rich agere- gales ute deformed in the plane o£ the pro- minent mica schistosity (S,) resulting in the development of small augen. Tn many pelitic units a prominent discontinuous layering occurs parallel to S, defined by the alignment of these augen. Andulusile porphyroblasts. which are 22) seen in thin section to postdate the augen development, also help to define this layering. Andalosite-rich pegmatites containing mus- rovite and corundum occur within this interval, Small-scale first- and second-generalion folds ate commonly present m the metasediments vdjioent to the pezmiatites, which are invariably strongly boudinaged, C WATTABERRI SuB-GROUP (new name) A marked change in sedimentation took pluce ufter the ueposition ef ihe Balquhidder Fornilion duc to the influx of fine-grained ctustics. These now constitute a sequence of essenlially phyllites or schists, metasiltstones und fine-grained metasandstones and are dis- cussed below under the name of Petrel Cove Formation, The succeeding characteristically faminuted and cross-hedded Middleton Sanu. Stone is Yrouped with the Petrel Cove Forma- lion 45 the Wattaberri Sub-group. named from the property called “Wattabers”. some 2.5 km northeaf Port Elliot. Perrel Cove Formation (new name) This formution is much less resistant to ero- sion than the Balquhidder Formation and thus forms | more subdued topography, [t occurs in low ¢lill lines between a point 0.75 km west of King Beach and Petrel Cove. aftee which the formation is named. Good outcrops can also be inspected at low tide in Rosetta Huar- boron the NW side of Rosetta Head. All parts of the formation in this area are readily accessible. It can be regarded as one of the key areus in the State where so many aspects of the effects of metamorphism and tectonism of a sedimentary sequence can be demunstrated clearly. All efforts should be made to preserve this stretch of coastline as a geological monu- Hent. Vanous aspects of the geotory of parts of the sequence have already been discussed by Browne (1920). Bowes (1954), Hobbs & Tal- bor (14956) and Talbot & Hobbs (1968 and TV69], A sequence of folded porphyroblastic and sindalusite-cordierite schists constitutes the hase of the Petrel Cove Formation. These confor- mably overlie the topmost unit of the Balqu- hidder Formution which 1s composed of a sequence of fine-grained metisandstones and mejasiltytones, The schists exhibit a well- developed gugen layering (S,) axial plane to F, tolds. which are cleatly outlined by the hedding (S\,) ws is seen in Figs. 35 and 36, Tn the saihe Oulerops (ste especially Fig, 35) verv thin light-coloured layers pervade the schists and appea as a senes of thin closely spaced B. DAILY and A. R. MILNES stripes (S,) at a low ongle to the auger layer- ing. These stripes define what is herein termed a “striped” layering (see also Talbot & Hehbs, 1968), We regurd this “striped” layering as having developed by alteration along tensional (ractures post-dating the F, folds. Note also that tn the same outcrop (Fig, 35) there arc “pincth-and-swell” pegmatitic layers parallel io the “striped” Jaycring and along which disloca- tion hus taken place, In several areas more than one set of “striped” layering can be recognised. A well laminated metasilistone sequence (Fig. 37). parts of which are strongly folded, oecurs on the wave-cut platform pbove the basal anulalusite-cordierite schists, Mics porphy- roblasts, light-coloured augen m S,, and an in- frequent “striped” layering show up in parts of this succession. Dislocation of bedding paral- lel to the stripes is ugain evident in some aul- craps.. Stratigraphically above are porphyro- blastic metasiltstones and schists with intervuls Showing either isolated augen in S, or with dugen sufficiently concentrated to produce an augen layering in S;. Very fine-grained meta- sandstones are interbedded with these. On King Point the beds are well laminated and exhibit small-scale sedimentary structures (Fig, 38). Near this locality some calc-silicate layers occur parallel to the bedding and shaw « cleavage/ bedding intersection plunging towards the south, These beds strike across the bay rowards Petre] Cove, Along the coast between King Beach and the contact hetween the Petrel Cove Formation with the Encounter Bay Granites on Rosetta Head, the incompetent metasediments within the Petrel Cove Formation show numerous meso-scule Folds of two generations, The folded sequence consists of very fine grained meta- sanistones with interbeds of metasiltstones and crenulaled schists. Numerous deformed sepli- mentary structures such us those in Pigs, 39 and 40 are common. Similar sedimentary struc- tures have been figured or discussed by Hobbs & Talbot (1966) and Talbot & Hobbs (1969), The common occurrence of “striped” Llayer- ing (Figs. 39-47) which, in a thick homo- geneous rack type, could passibly be mistaken for bedding has heen mentioned above. This layering is markedly refracted across the boundaries between the metisandstones and the andalusite-cordierité schists. The layering is not only discontinuous hut may even show a feathering effect fPig. 454, aguin u feature sug- gesting that rt developed in response to ten- sion. In addition, it formed afler the F, feld- GEOLOGY OF TYPE SECTION, KANMANTOO GROEP ICAMARIAN) 32] ing phuse because faint stripes cut straight through strictures on the tap of heds deformed by that phase of folding (Fig. 39). In many andalusite-cordierite schist intervuls, especinlly along the coastline immediately west of Petrel Cove, the “striped” lavering has been folded on a amall scale about an axial plane purallel 10 the crenululion cleavage (S.) (Figs, 43 and 461. Many of these andalusite-cordicrite schists show either a preferred concentralion ur a depletion of andalusite porphyroblasts paraile} to the “striped” layering (Fig. 47), Cummozoic and Permian sediments (un- colonred in Fig, 4) blanket mast of the region between Rosetta Head and the hills lying to the nerth of Port Elliot. Over this distance no rocks helonging to the Wattaberri Sub-group are known to Getcrop on the coast, However, in a section between Brown Hill and Wattaberri we have inferred a houndary heltween the Bal- qguhidder Formation (containing some blue- black carbonaceous and pyritic phyllites) and an overlying dominantly phyllitic-metasiltstone sequence identified as the Petrel Cove Farma- tion (Fig. 48). Despile a prolonged search in the area, we have been unable to locate anda- lusite or other distinctive melamornphic minerals so characteristic of many parts of the formation in its type section between King Tomt and Rosetta Head. Stratigraphically above these racks are metasandstones of w dis- unetive facres which we call the Middleton Sandstone. This formation is best examined in the Middleton quarry and on Middicton Beach Metasandstones of an identical facies and stratigraphic position lie in contact “ith the Encounter Bay Granites on the eastern end of Kangarcur 1, We have been unable to locate a contact between the Petrel Cove Formation and the Middleton Sandstone une ta imperfect qutcrop Nevertheless, 9 tentative houndary has been positioned as shown in Fig, 4. Rocks shown as Middleton Sandstone pre characterised hy the presence of epidote-rich bands. Middleton Sanestane (new name} The best section of Middleton Sandstone is seen on the wave-eut platform in the vicinity of Middleton (Pig. 4). These outcrops. which are totally isolated from other Kunmantoo Group rocks, consist largely of grey-coloured fine-prained metasandstones which are gener- wily Ughter in colour and mure quartzese than the bulk of the metasandstones found in the Kinmunton Group, with ie exception of some of the Inmun Hill Sub-group metasandstones,, for example those of the Backstairs Passage Formation, The metasandstones ure typically very well-laminated and are commonly cross- bedded wilh sets up to 1.2 m thick (Fig. 49) and with an indicated current direction gener- ally from the west throughout much of the sequence. In some of the higher parts of the outcropping sequence, more random current directions are indicated, Some slumping down the direction uf the cross-hedding is evident. Breaking the monotony of thie well-laminated sequence ure intervals with minor sedimentary structures. mainly small-scale current ripples, which include some starved ripples involving material of somewhat different grain size. There wre also rare metasandstone feds up lo 0.5 m thick containing angular pbyllitice clasts up ta 30 em long and 15 cm thick, though generally the clasts are platy and less than 5 cm acress, They represent the ripping up of partly- indurated mudstones by strong currents and their subsequent depositinn in scour-channels after very limited twansport. The only other metasediments present are a Few metasiltstones, up wo 10 m thick, containing chlorite and actinolite, One of the mast conspicuous features of the sequence is the prevalence of pale-green epidote-rich sepreeations which are developed consistently throughout the succession, Albitised bleached zones of alteration ate also presence. Most of the epidote-tich segregalions vecur eilher in bands or as lenticular patches and nodules parallel to the bedding (Figs. 50- S52) but some epidole occurs in association with quartz-chlovite-feldspar pegmatites that are de- veloped in fractures and boudinaged zanes All beds in the sequence fuce north. Obser- witions show that the frequent occurrence of overturned southerly dipping beds is due solely jo warping locally developed along the sirike. Practute-cleavage/ bedding intersections indi- cute that the heds belong to the southern lind of a synelinc plunging shallowly towards the east, This syneline is a second-generation fold as Shown by overprinting relationships in Midd'eton Sandstone in the Middleton qitirry The recognition of Jarge second-generation folds in this area significantly adds fo the small number of macroscopic F., folds reparted fror elyewhere within the Mr. Lofty Ranges hy Offler & Fleming (1968), No upper boundary to the Middleton Sand stone is known on the Fleurieu Peninsula, and consequently this formation comprises the youngest Kanmanino Group rocks in the 322 B. DAILY and A. R. MILNES eastern Mt. Lofty Ranges. Because the En- counter Bay Granites exposed at Port Elliot seem to have intruded rocks of this formation, a substantial sedimentary cover must have existed above the Middleton Sandstone at the tine of granite emplacement and metamar- phism. This cover is likely to have embraced rocks ef Middle Cambrian to possibly Karly Ordovician age, as rocks spanning this sugaes- teil lime interval occur on Yorke Peoinsula (Datly 1969) and in the Flinders Ranges (Daily & Forhes 1969). D. INTRUSIVE Basic Dykes Two groups of basic dykes that have in- (ruded the Kanmuntoo Group within the type section wre shown in Figs, 2-4, The dykes of the first group are transgressive fine- to meditim-grained metadolerites, Similar rocks have intruded the Encounter Bay Granites at Rosetta Head and Port Elliot. ‘The second group consists of hasic dykes exlensively contaminated by meta-sedimentary rock material. One such dyke containing large feldspar megacrysts. intrudes Balquhidder For- mation metaxediments along the coast cast of Tunk Head (Fig. 3). This dyke was described by Madigan (1925), A second contaminated husie dyke-rock occurs in the line of ancient coustul cliffs backing Tunkatilla Beach, but it is poorly exposed. Sirnilar contaminated basic dykes have intruded the Middicton Sandstone dong the south cous: of Dudley Peninsula (Kingarco I), west of Cape Hart. The results of our investigations of (hese rack lypes will be presented tna subsequent communication. Structure A lar Structruse of He Mera-sepimMen- TARY SEQUENCE An Interpretation of the geological structure of the Lower Cambrian rocks exposed alone the south coast of Fleuricu Peninsula between Campbell Creek and ‘Tunkallly Beach has been even in Daily & Milnes (1971a). This sequence. involving the upper parts of the Nor. manville Group’ and the lower parts of the Kanmantog Group, is contained within a NE plunging regional anticlinal structure which is overturned io the NW [Fig. 2}. On the normal eastern limb of this fold between Madigan fn- let aud Tunkalilla Beach, all the mapped mucroseale folds are believed to be first- generation (F,) structures, Generally they conform to the style of the regional fold, and indeed to the style of folds developed in the Late Precambrian ‘lorrens Group rocks in the Houghton area described as B, folds by Talbot (1964), and most of the folds described by Omer & Fleming (1968) as F, folds within large areas of the Mt. Lofty Ranges. They are mainly inclined and asymmetric with eastern bmbs of unticlines longer than western lintbs. and with axial planc cleavages which dip steeply to the SE. In many instances, disloca- tion of the overturned western limbs of -unti- clines has taken place along faults thar tend to purullel Lhe axial plane schistosity. All struc- tural data for this section of coastline are sum- marized in Fig, 5 which shows the following: (9) poles to bedding (S,)) indicate a fold usis estimated to: plunge towards 047° at a low angle, although mesoscale F, folds plunge al Variuble angles towards both the NE and the SW: (b) intersections of §, with cleavage (8,), long axes (L,) of phosphatic nodules Cin the Heatherdale Shale), and the elonga- tio of boudins resulting from: the defor- mation of cale-silicate bands within the overlying Kanmyntoo Croup are parallel ta the axes of mesoscale F; folds; (c) F, fold axes and the long axes of phos- phate nodules und ealc-silicate boudins define a great-circle distribution which may be the result either of refolding or of inhomogencous strain; {di a lineation defined by the elongation of calcite and mica crystals on $, surtaces {not heddiny surfaces as reported in Daily & Milnes 1971u, p. 207) in eal- eureous and pelitic intervals respectively, pitches up to 20" more steeply than 1,,, und is now interpreted as a first-gencra- tion structure Li’ (not a-sccond-generation xtruciure as suggested by Daily & Milnes 197ta). The preferred orientution of horn- blende poikiloblasts and. chlorite porphy- roblasts. on §, surfuces in cale-siliegte hourtins. and pelitic tntervals respectively is approximately parallel to Li’, but its significunce is not understood. ' This new name is defined herein to inchide all the Lower Cambrian sediments between the bise of the Mount Ternble Formation and the base ot the Carritkalinga. Head Formation as mapped in the Sellivk Llill-Normanville area by Abele & MoGowran (1959) and revised by Daily (1963), GEOLOGY OF TYPE SECTION, KANMANTOO GROUP (CAMBRIAN) FOLD. PHASE PLANAR ELEMENT LINEAR ELEMENT : S + surface Spe peaning Tihat generatien elructures +y S)=Schielmeity Ly 7 Uheation ar eis ut dott iw My with Sy as welal su fface by = olnerar 1 Plonyation in Sy Second generation alruciures hy S.=—crenulalion 7 cleavage, Asia! Burtace ta Fy tots. Lo bineation gr Beis af told or granulation ia, or Wilh S; ay ania Surtace™ [i renresents ¢elimated direction and plunge of fold aais, wr ah. a Peo AyHO47 s1meeD® Pa ms A Miage i" | *., / \ i 4. : - f “\ t d y ~s e Poles to Se A Poles to S- se ee + F Fold gees 2 &, Sleavage/hedding jntersecvons VY lLoeasleite, cise slangailyds im Sy Fig. 5. (Above)—Table of structural elements and corresponding symbols utilised in the text. (Below }—Equal area projection of struc- lural daty for the section between Madi- gan Inlet and Tunkalilla Beach. Structural data for the remainder of the type section and the region east to Middleton are as follows: (i) Turkalilla Beach to Rosetta Head All the macroscale folds mapped and most of the mesoscale folus observed to the east of Tunkalilla Beach are interpreted as F, struc- lures, They cojiltrast with the style of the regional fold ta the west (mentioned above) in that the western anticlinal limbs are not over- turned, The folds are however mainly asvm- metric with western antichnal limbs stecper and shorter than the eastern limbs although towards Rosetta Head the folds tend to be more upright, symmetrical and apen (Fig. 36), In yeneral, folds in metasandstones are oper 223 structures Whereas folds in the metasiltstones and schists. particularly within the Petrel Cove Formation, are smaller scale structures that tend to be moderately tight and upright. The transition [rom one style to another within the metasandstones cannot be pin-pointed, Our ob- servations suggest that it is gradual, and it seems significant that the highly appressed F, folds are characteristic of the oldest parts of the stratigraphic sequence, whereas folds in progressively younger formations are more open and upright. ‘Vhe validity of this proposi- tion is strengthened becatise on Dudley Penin- sula, Kangaroo L.,.and along the Mount Barker Creek. comparable situations pertain on the eastern limb of the regional anticline. The axial plane schistosity in F, folds is defined by the preferred orientation of micas which commonly enwrap small quartz-rich aggregates and, in some localities east of New- land Head, cordierite porphyroblasts. The resulting augen define a unique augen-layering parallel to S, (Figs. 34 & 35; Talbot & Hobbs b9G8). In the schists est of Newland Head there is a distinct but often discontinuous linea- tion due to the elongation of augen on §, sur- faces (Fig. 53). ‘This lineation is decidedly different in orientation from that of the inter- section of S, and 8, surfaces and the axes of F, folds. A weak crenulation of S, is apparent in phyllites near Coolawang Creek and bevomes more distinct eastwards, This crenulution pro- vides evidence for the overprinting of first- generation structures, In some areas there is a penetrative strain-slip cleavage (Sa) which is axial plane to mesoscale second-gencration (F.) folds, Such folds are most cofispicuous adjacent to pre-F., metamorphic pegmatites (Fig. 54), They tefold small-scale F, folds (Figs. 54 & 55) and are responsible for the local variation in the plunge of F, fold axes from NE to SW. It should he noted that in the Rosetta Head region, Talbot & Hobbs (1968, p. 584) have pointed out “that several sets of crenulation cleavage are developed lacally”, We have mapped only one crenulation cleavage (S,) in that area, The distinctive “striped” layering (S,) referred 10 above is best developed just west of Petrel Cove, Talbot & Hobbs (1968) also reported ifs occurrence in the Kanmantoo Mine area in metasediments assigned by Duily & Milnes, (1972a) to the Tapanappa Formation. The “striped” liyers are zones of alteration and consist predominantly of quartz and plagioclase 224 wilh seme muscovite. They are up to 3 tm wide, anu ure often bordered by thin biotite- rich zones. I tiddition they may show a median biotite nu/ or qual'tz-filled fracture (Fig. 56) Althaugh ihe “striped” layering cuts across S,. i fellct Sy schistasity. outlined by the preferred orientation of muscovite and rare biotite, can be seen within the “striped” layering. Struc- tural relationships show thar the layering ts not only post, but clearly pre-Fa (Figs. 43 & 46), Talbot & Hobbs (195, p. 585) sug- pested thal the “staped” layers are “hon dilata- tional and represent same form of differentia- tion process. in situ’. In wew of the presence of a central fracture within the “striped” layers, the refraction of Inyenng across bedding, and Fouthering, we can only conclude that these structures ure dilatational anid wre due to ten- sion and subsequent alteration adjacent to the Fractures, Alt structural data. collected between Tunka- lilla Reach and Rosetta Head ate given in Fig. ® a=d. This shaws the following: Poles 10 3S, show a great-circle spread and indicate a [old axis estimated to plunge at 25> towards 200° (Fig. 6a), This is supported by the attitudes of Ly lineations defined mainly by the intersec- fiun of S, ad.S, surfaces (Fig. 6b), However, uxes Of mesoscale Py folds are distributed about Wo point maxima, indicating plunges towards the NE and the SW at shallow angles (Fig. 6c). This suriition in plunge together with the significant spread of poles to S, (Fig. fe) may indicate refolding of the first-genera- ijon ytructures, or may be dug to differential strain. Ls lineations (the axes of crenulations jn S,) plot as a diffuse maximum giving an estinvaled plunge towards 165" at 63° (Fig, ful = (ii! The Brawn Hill drea In the Brown Hill area, large scule NE plung- ing asymmetric F, folds in Balquhidder Forma- Gun metisedimenis occupy 4 narrow NE trend- ing zone. The folds gre upright, and have the open style typical of F, folds in metasandstones in the eastern part of the type section. The axial plume schistosity is defined by the pre- ferred orientation of micas, A lineation formed py the intersection ol 8, and S,, surfaces is parallel io F, fold axes, $, surfaces in pelites contain a mineral lineation defined by the pre- ferred orientation of micus. This lineation has a sleep southerly pitch in $,, and is interpreted B, DALLY and A. Ro MILNES usu firsi-veneration seructure (Loy. It is best seen in the Lincoln Park quarry, south of Brawn Hill. The structural elements meastired in this arca ure plottel in Fig. Ge, Poles to Sy lie along a greal circle, and imuicule an Fy fold axis esti- muted to plunge at 35° towards U51°. This is supported by the attitudes of 1,’ lineations. Two measuted L,’ lineations plinge steeply towards the south, Gil The Middletant A rect Fust of the Brown Hill area, Fy, folds in metasediments assigned to the Petrel Cove For- mation and the Middleton Sandstone have been overprinted by large- and small-scale Hy folds that plunge at shallow angles towurds the SE The relationships between F, und Fy siruc- lures, both of which exhibit varving deerves. of development in the area, wre besr examined tn the Micdkdlelton quarry wbout L4 km NW ol Middleton. SE plunging F.. lolds are the deminant siruc- tures in the Middleton quarry, und are moderately uppresstd, inclined folds im which the northern limbs of anticlines are longer thin the southern limbs, and tend to he overturned (Fig. 57). The larger folds contain small-scale refolded Fy folds in pelitic units (Fig, 48), A prominent set of fractures occurs in 14, folds in metasandstones and purallels the weakly developed axial plane schistosily of these folds (Fig. 57). The intersections of the fractures {S.,) with the bedding detine wu ridge- und-furrow lineutian which parallels the F, fald axis and is referred to here as La (Fig. 59). These fractures have lirvely controlled albitisition and the ¢mplacement of thin peg- matites. They have also been planes of past- alternation movement ulong which either thin cuatings of fibrous hornblende or hrecciated zones have developed. Inspection of the metasediments in the Middleton area shows that three schistosities ure present. 4 well expressed axial plane whit tosity in some mesoscale folds in fine grained metasandstones can be seen in thin sections to crenulate a poorly developed older schis- losity that is approximately parallel {o bedding (Fig. 60). Moreover, an examination of the axtal plane schistosity surfaces. shows u con- spicuous mica-streaking lineation tbat is not parallel to the fold hinges (Fig. 613. The presence of two schistosities in these folsis = Mésosealé Fo totds are Wneommon. but gencrally oceur nenr jhe margins of pre-Fu pegmatite dykes in jhe Petrel Cove Formation, No wllempl was made to measure their attitudes in such localities, GEOLOGY OF TYPE SECTION, KANMANTOO GROUP (CAMBRIAN) 225 MN + Poles to So 8,= 200° ptunge 25 ® L)= cleavage/bedding intersection Vi Le=calc-silicate rod MN elongation MN 4 Poles io S, o Ll + F, Fold axes 2 A FoFold axes A,= 051" plunge 35° 8,= 118° plunge 50° Poles to Sq Pol Poles to Sj * Hes: te Sg dene Ly Lif Fig, 6. Equal area projections of structural data. a-d, Tunkalilla Beach to Rosetta Head; e, Brown Hill area; f, Middleton quarry. 22 RB. DAILY and A. R. MIT-NES would normally identify the folds as secund- generation structures. However, small scale Fy folds in the Middleton quarry are characterised by a poorly-developed axial-plane schistosity (S) that overprints a developed schistosity parallel to bedding. In these folds. it is the older schistosity that con- Wing @ prominent mica-steeaking limeation whieh as similar in nature and orientation to lig L,’ lineation recorded in metasediments in ihe couslal part of the type section and in the Brown Hill area In the Middleton quarry. Lhis mica-streyking lineation is readily seen on the surfaces of F, folds, where it is oriented at a significant ungle to the intersection bewween bedding and S, (Fig, 621. In view of these ab- servations, we presently interpret the meso- seale folds of uncertain uffinitics. os first- pencration siructires that formed in metiasedi- ments containing a pre-teetonic bedding pline schistosity, and the accompanying prominent micu-streaking lineation as by‘. F,, olds were nol observed in the rather poor exposures outside the Middleton quarry, o i the small quatty expasures NW of Port Ri hat, In these foculities, folds also hesitantly inter- ptered as first-generation structures form the dominynt sttuctueal clements. They are best seen i the exposures to the north of the Middleton quarry. They are inclined, and plunwe jd steep angles towards the SE. The uXial plane schistosity is a pronounced mica- preferred urientalion which again overprints a pourly preserved presumed pre-tectonic bed- din-plune schistosity in some specimens, The imerseation ot bedding with the axial-pline sclisiusity is parallel to the axes of the folds, However, a prominent micd-streaking lineation oa schistusity surfaces pitches up to 20° from the intersection between bedding, and the axtil- plane schistosity- S, Satiaces in phyllites of the Petre! Cove Formation exposed inthe quarries NW of Port Elliot and in the cuttings along the Crow's Nes! road cxhibil a fine-scale crenulation. ‘The creou- lalion appears to have a similar orientation to the conspicuous mica-streaking lineation { pre- sited L,') on $, surluces in metasandstones in the Middleton urea, but ts interpreted a3 a secomiu-poueration structure. Theexposures of Middleton Sandstone along the coasuine at Middicton are dominated by F,, Structural clements. A proninent ridge-and- lurrow linewtion (L.) indices a shallow easterly-plunging fold. This ayrees with the moderuicly well-: orientalion of the fold axis of the only Fold recorded along the beach. The geometry of the structural elements for the Middleton sree are given in Figs, 6f, Tae und show the following: Poles to S, measured in the Middleton quarry (Pig. 6F) do nut re- flect the attitudes of firscgeneration folds, burt define and F. fold axis estimated to plunge towards LL&° at SO". This agrees. with the atti- tudes of measured Fy fold axes and L,, ridye- and-furrgw tinealions (Mig. 7a), In addition, it is Consistent with the distribution of poles un S. fractures in melasandstones. The distribution of measured mica-streaking hnewtions in the Middleton quarry indicates an estimaled plunge towards 122° at 65°, whilst the attitude of the related schistusity indicates a stecply-plunging inclined style for folds herein interpreted as first-generation structures (Fig. 7b). The structoral elements Sy, and 1... measured in the exposures at Midulleton Beach define an F., told axis estimated to plunge at 28" tawards NYO", and this is supported by the attitude of one mesoscale F,, fold uxts (Fig. 7c). In all other parts of the Middleton area, presumed first-generation structures are domin- ant, Poles to S, define an B, fold axis csu- mated to plunge at 60° towards 142° (Tig, 7d). The rather diffuse distribution of S, poles on the western side of the diagram may reflect the influence of second-generation folds, ‘The attitude of the F, fold axis is confirmed by the distribution of mica-streaking lineations und the attitudes of poles to the axiul-plane schistosity (Piz. Je), and approximately coincides. with the orientation of presumed first-generation structures recorded in the Middleton quarry. BL. STRUCTURAL RELATIONSHIPS OF THE Encoun?tit Bar GRANITES The contact between the Kanmantoo Group metuscdiments (Petrel Cove Formation) and the Encounter Bay Granites is exposed on Rosetta Head and Wright |, bat is best examined on Waiglit 1. because of the excellent exposures there. Our observations of the rela- tionships at this contact can be summarised is tollows. {) The marginal phase of the Encounter Bay Granites is a coarse-grained meguerystic granite, Megacrystte granite sheets of variable thickness and grain. sixe form apophyses from the main granite mass, and ure laracly concordant with bedding in the Petfel Cove Formation metasedi- GEOLOGY OF TYPE SECTION, KANMANTOO GROUP (CAMBRIAN) 227 B= 18° Plunge 50° Poles to So o bg 4 F53Fold axes ¥ Limica streaking 4 Poles to $4 MN MN o B:=O90" plunge 28 B:=142° plunge 60° » Poles ta So » Poles to Sg on lg A FoFoid axes MN B,= 142° plunge 60° ¥ Limica streaking & Poles to S, o Poles to Sg Fig. 7. Equal area projections of structural data. a-b, Middleton quarry; ¢, Middleton Beach; d-e, Middleton area excluding the Middleton quarry and Middleton Beach. 4 rm x ments TFig. 63). The granite sheets dre murkedly boudinaged in places, [h) Petrel Cove Formation metasediment, in contaer with the megacrystic granite, hoth on Wright I. and Rosetti Head, are lim- inated metasiltstones, A paucity af porphy- roblastic andalusite and cordierite schists adjucent tn the contact compared with their abundance at lower straliyraphie levels Within the formation further from the granite was noted, (c) A prominent schistosity ($4) occurs in the Petre] Cave Formation metusediments anil @ pafallel schistosity occurs In the borders and constricted portions of \he boudinnged megaerysiic granite sheets (Fig. 64). The same schistosity is variably developed within the marginal metre of the main granite mass. Within the affected granite, the schistosity (Fig. 65) is defined by al- ternuting laminae of recrystallised biotite and quartz, which cnwrap latge potash feldspar and pligioclase megacrysts. Al- though recrystallised along their margins, these megucrysts retain their original inter- nal structures: some have been rotated. The schisloxe gronile muy be regarded as a protomylonite using the terminology of Hiseins (1971). However, we believe that the schistosity has been imposed during regional deformation at a moderately high temperature. The variable development of the schistosity in the srinite along the contact. 1ogether with its absence from the internal parts of the pluton, gre duken ws eVidence for the high yield strength of the granite at this time, and suggest thit the pluton possessed sigh bouy properties during the regional deformation, Metisciliimentury-rock xenoliths within the megacrystic granite awoy [rom the con- act ure devaid of deformation structures and, with few exceptions. tectonically tm- posed miga-preferred orientations. More- aver. xenoliths containing andalusite or corilierite porphyroblists have not becn observed. (el Structures younger than the S, schistosity occur wilhin the metascdiments and wranite sheets on Wright 1, and include fine scale crenulations in the 5, schistosity. Broad scale kink-folding of bedding add thin eranite sheets has alsa been noted, On the southern side of Wright 1., a cata- clastic zone crosses the contact and has deformed the S$, schistosity. Catactastic (al) Kk IALLY and A, Re MILNES TOAtUIES are CONspicuoUS in the granite. and are strikingly different from textures in the schistose granite. C, Summary The observations anc meastirements of structural elements indicate two malt phases ot deformitiun of Kanmantoo Group metascdi- ments in the type section. With the exception of parts of the Middleton area, first-generation structures ate dominant. However, second-gen- eration structures are moderately well devel- oped in the Petrel Cove Formation between Rosetta Head and King Beach, and are domin- ant in. Middleton Sandstone in the Muldleton quarry and at Middleton Beach, There ate several structural observations thut will only be adequately explained after the camipletion of a more comprehensive investi- gation of the structural geology of the Kammun- too Group than was attempted here, Such ob- servations include the variable development of structural elements in the type section, and the variability in style aod urientation of first generation folds. Notwithstanding, the data presented herein provide an adequate basis for an interpretation of the time of emplacement of the Encounter Bay Granites in relation to the structural deformations recorded in the con- liguous Kanmantoo Group metasedimentary rocks. The following observations are con- sidered most pertinent to this discussion; (a) The prominent schistosity that aceurs with- in some parts of the megacrystic granite along its contact with the Kunmuantoo Group metasediments, and in boudinaged grantle sheets: wilhin metasediments auja- cent to the contact, is parallel 10 the S, tchistoxsity in-the metasediments; and metasedimentary-rock xenoliths that occur within the meguerystic granite away from the contaci. are. with few cxeeptions, de- void of lectonically imposed mici- preferred orientations, Thus the Eneounter Bay Grnites ate con- sidered to have been emplaced prier to the main phase of first-generation deformation and are, in (his sense, pre-tectonic, The texture of the schistose granite indicules that the meyi- crystic granite had completely crystallised prior to the imposition of the $, schislosxity during the main deformation phase, Although second-generution structures have overprinted the 8, schislosity in the metasedi- ments and in ihe biotite-rich borders of the granite sheets on Wright 7, their sporadic de- velopment bas prevented ar) assessinent of their fh) GEOLOGY OF TYPE SECTION, KANMANTOO GROUP (CAMRBRIAN) effect nn the granites an a broad scale. On the other hand, second-geheration structures pro- vide an important teference point in a discus- sion of the relative ages of pegmutite and meta- dolerite dykes. For example, hoth peematites und metadolerites occur ag transgressive dykes within the Petrel Cove Formation, and do not exhibil first-generation structural elements, However, they have heen folded and houdin- aged during the second phase of deformation, Ir fact, second-generation structures, inchiding mesoscopic folds and an obvious crenulation cleavage. are commonly hest developed immed- dutely adjacent to these dykes, On the basis of these observalions, the pegmatites and meta- dolerites appear to post-+late the first-generation folding and pre-date the second. Similar rock- types idtrudiog melasediments further west in the type section are probably of the same age, although this cannot be confirmed because of the iipparent absence of second-generation siructures in these areas, Metamorphism Published studies on the metamorphic pet- rology of the type Kanmantoo Group have centred around the metasediments in the vicinity of Rosetta Head. From that area Browhe (1920) first recorded the presence of indalusile und cordierite . Later, Bowes (1954) subdivided these metuseciments into three groups, namely quartz-blotite schists, anudulu- site and cordierite schists, and albite and chlor- ite schists. Both Browne and Bowes regarded the metamorphic assemblages as a consequence of the emplacement of the Encounter Bay Granites. On the other hand, Offler & Fleming (1968, p. 259) recognised “snowball” Internal fabrics in (he andalusite and cordierite porphy- roblasts in this area and suggested that “since the Victor Harbor Granite does not appear to have been emplaced forcefully. such fabrics could only have been produced during a defor tation phase before the intrusion of the gpran- ites. As shown below cordierite is mainhy pre- (o warly svn-F, whilst andalusite is late syh- to post-F, and pre-F,,, For that part of the type Kanmantoo Group west of Tunkalilla Beach, Daily & Milnes (T971u) concluded that the metamorphic arnde lay between the almandine and slaurolite isa- studs as defined by Winkler (1970+, and with- in the andalusile-staurclite zone of OMer & 2349 Fleming (1968). Although our estimate: of the prade still stuns, we realize that our inter- pretation of the metamorphic history was over- simplified. In the present context we have uttempted to link the various mineryl assem- blages to readily identifiable structural elements in the rocks and thus deduce the retative time relations between crystal growth and deforma- tron in the fashion of Zwart (19631, Spry (1963) and Offer & Fleming (1963), How- ever, this method cannot give a measure of the time between the various structural and zon- comitunt metamorphic phases, nor can it allow one to assess the time tiken for the essential metamorphic reactions to produce the mineral ussemblages seen today. Tt is most likely thr the various recagnisahle metamorphic phases discussed below are but part of a continuum, It should be noted thal all the following ob- servahions and the conclusions drawn from them pertain only to rocks in the type section of the Kanmantoo Group as specified by Sprigg & Campana (1953) and jin our extension of the type section into the region between Brown Hill and Middleton Bench, which we regard 48 helonging to the uppermost part of the Kan- mantoo Ciroup in the castern Mt. Lofty Ranges. Within the Kanmantoo Group conspicuous metamorphic mineral assemblages are uncom- mon, and are confined mainly to thin cale-sili- cate banifs and lenses and to satne pelitie inter vals, All nictusediments except the phyllites re- tain aspects of Iheir original detrital nature despite the deformation and metymorphism, The following assemblages of minerals? scem to be representative of the vurinns rock types wilhin this region: (a) metasandstones and metasillstones— quartz + plagioclase + biotite ++ musco- vite = calcite + chlorite 7 garnet scapolite = epidete; (hd phythtes— quariz — plagioclase + biotite + muses- Vile = chlorite + varnct + andalusite + cordierite; (¢) carbonaceous and sulphide-rich phyilites— quartz + plagioclase + muscovite + pyrrhotite + graphite; cale-silicates— quariy | plagioclase + hornblende = gar- net + chlorite + calcite = biotite + mus- covite = pyrrhotite “= epidote. (d) * Offer & Fleming (196%) have reported fibrolite in many schists within the Mi Lofty Ronges. We had nal seen thts mineral in our thin seetions until Dr. R, Ofer located am isolated patel in a thro seciion of metasandstone collected 200 m east of Bollaparadda Beach, 134 AS uv fesult of a petrographic study of the Kanmantoo Group rocks collected during our traverses, ihe following scheme of progressive mctamorphic crystallisation is envisaged: A. Pre- te Syn-F, Metamorphic Crystallisation Metamorphic elements attributed to this phase of crystallisation inglude small quartz- rich aygtexales, groundmass. biotite and mus- covite, porphyroblasts of biotite, andalusite and rare chlorite, and cordierite augen, the latter commonly altered to a brownish-yellow clay mineral determined hy electron probe analysis as kuolinite. BiotLe porphyroblasts occur with ground. mass micas throughout the region, but the quariz-rich aggregates seem to be restricted to the remon hetween Tunkalitly Reach ard Bn- counter Ray. Cordicrite is more severely restric- ted, bein found only in some phvilite hands in the upper part of the Balquhidder Forma- tien, and mm the Petrel Cove Furmation neni’ Rosetta Head Metamorphic clements of pre-F, age ore uncommon but include many small quartz-tich ugercgutes containing feldspar, opaques and micas (Figs, 66 & 67), Their grain size is always finer than that of the same minerals in ike groundmass. They form augen which generally contain a randem internal mica fab- Tic and arc enwrapped by the well developed mica schistosity. However, same quurtz-rich uugen that have been observed with a poorly- oriented mica fabric may be partly syntectonic. Some cordicrite augen in the Petrel Cove Fors mation exhibit a random inclusion fahrie und represent pre-P, crystallisation. Metamorphic elements formed during the first. phase of deformation include the minerals that define the S, schistesity, namely biotite and. muscovite. Fer the most part, syn-F, bio- tite and’ muscovite are fine grained, Medium- grained biotite and chlorite parphyroblasts of this age have been noted, 5, is also commonly marked by u preferred orientation of opaque mineral laths, for example Fig. 66. Many cor- dierile wugen which are enwrapped hy $4 show oriented inclusion fabrics, that are cither planar and inclined at a significant angle to 8. or are S shaped (Figs. 67-70). Such fabrics are con- tinuous with the 8, schistosity in the enclosing rock. Moreover, as inclusions within the por- phyroblasts are finer than the same minerals in the groundmass, we conclude that cordicrite crystallised and was rotated during, the early Stages of formation of 3, - B. DAILY amd A. R. MILNES Andalusite commonly occurs as S-shaped poikiloblasts containing S-shaped inclusion- trails that are continuous with the external S$, schistosity (Fig. 71)_ Such poikiloblasts are the result of late syn-S, crystallisation ond rotation, In some cases the outer margins of poikilo- blasts cut across this schistosily and must ihere- fote represent post-S, crystallisation (Fig, 72) H. Past-Fy Metamorphic Crystallivation The major porphyroblastic crystallisation appears to have occurred during the post-F, and pre-B, static phase when andalusite, gur- net, hornblende, biotite, chlorite, muscovite. scupolite and epidote crystallised in rocks of appropriate lithology. These minerals cut across the groundmass S$, schistosity, but are de- formed by the $. crenulation cleavage in rocks in which this structure is developed, The fol- lowing conspicuous minerals aid mineral assemblages are characteristic of this meta- morphic episode: ta) calc-silicates— hornblende “4 plagioclase + chlorite + epidote, metasanrstones and metasilistenes — muscovite + garnet = chlorite + epidote; (c) phyllites—— = jndalusite = chlorite = garnet + scapolite + biotite. In addition, {here are several miner com- poncots such as tourmaline, some opaque minerals and sphene which appear to have crystallised across the groundmass $5 schis- fosity, and are similarly attributed to this meta- morphic episode. Post-5, andalusite occurs both as over- growths on svn-S, poikiloblasts (Fig. 72), and as poikiloblasts that have overgrown the groundmuss §, schistosity and have retained relicts of this in the form of oriented opaype laths and quartz grains (Figs, 73 & 74), In addition, post-S, chlorite (Figs. 75 & 76) and less commonly muscovite occur in phyllites and metasiltstones throughout the type section as Poikiloblasts that have grown across $4. Scapo- lite occurs as small porphyroblastic clots that appear to have grown across 5, within meta- siltstones, 1 kr east of Coolawang Creck- Porphyroblastic zoned garnets (Fig. 77) may occur with minor muscovite, chlorite, epidote and tourmaline in mcetasiltstones and metasand- slones throughout the lype section, These have eTown across the S$; schistosity. Such garnets aré conxpicnous in the heavy mineral sand suites along the southern coastline. gatmec (b) muscovile = GEOLOGY OF TYPE SECTION, KANMANTOO GROUP (CAMBRIAN) Although an interpretation of the textural relutionships im most rocks éiggest that the crystallisation of cordierite preceded that of undulusite, co-exisling post-F, cordierice poikiloblasts and andalusite euhedra occur in pelites within 1 m of a metadolerite dyke about half way between King Beach and Rosetta Hew. As structural evidence indicates that the metadolerite intrusions are pust-F, but pre-F.,, the cordierite-andalusite assemblage is inter- preted as being the result of a local increase in temperature along the dyke margins. Post-F, culc-silicate segregations occur throughout much of the region and possess a weakly defined relict 8, schistosity that con- trasts with the better defined schistosity of the enclosing mietasedimeots. Hornblende poikilo- blasts (erroncously identified optically as actinolite by Duily & Milnes 1971a} occur in the cale-silicates and, at best, exhibit only a moderaic depree of preferred orientation parallel co the relict S, schistosity. Some horn- blendes. transverse to S, contain undeflected remnants of that schistosity, especially opaque faths. Zoned varnets occur in the cale-silicates ws subhedral poikiloblasts that cut across S, but these also have inherited the 5, schistosity- Post-P, metamorphic minerals that occur in peliles in the eastern part of the type section, where the S., crenulslion cleavage is best de- veloped, ure deformed by Sy. The cislocation of chlorite and undalusite poikiloblasts along zones commoniy defined by trains of opaguc minerals grains (Fig. 78), are especially evi- dent in pelites In the Petrel Cove Formation in which Sy assumes the characteristics of a stramn-slip cleavage, Many pegmiutites within the type section are composed of minerals that characterise the post-F, mineral assemblages in the host rocks. On structural evidence, such pegmatites are post-F; and pre-Fy and represent the “sweat” products concentrated in regions of low pres- sure gtadient (Rivalenti & Sighinolfi 1971)- Wall-rock alteration has been noted adjacent to some of these pegmatites. C. Conditions of Metamorphic Crysiallisaion A petrographic examination of Kanmantoo Group metasediments in the type section seems to indicate a relatively simple sequence of Metamorphic crystallisation, This sequence be- gan with the formation of quartz-rich agere- gates and the crystallisation of cordierite dunng the pre- to easly syn-F, phase of deformation, was followed by ihe late syn-P, crystallisation of andalusite and chlorite and ended with the 231 post-F; crystallisatioi ot andalusite, chlante, gamel, hornhlende, muscovite and scapulite, Offler & Fleming (1968) regarded the meta inorphic mineral assemblages Whtoughout much of the Mount Lofty Ranges as churacteristic oF low pressure, intermediate-type metamorphism, With reference to the aluminosilicate data of Newton (1966), they suggested that meta- morphism in the areas of highest grade occurred at pressures (Pigiai — Pang) between 3 and 4 kb and at temperatures in the vicinity of 650°C, The metamorphic minerals in the Kanmantoo Group metasediments in the type seclion are certainly consistent. with conditions of low presstire, intermediate-type metamar- phism, but are representative of lower tem- peratures und pressures than the assemblages upen which Offler & Fleming based their esti- mate. The crystallisation of pre- to syn-F, cor- derite and late syn- to post-F, andalusite in metasediments in the type section suggests that the conditions of metamorphisin at this time Were consistent with the andalusite-cordierite- muscovite subfacies of the amphibolite Facies (Winkler 1965). Of several possible para- geneses fnvolving the crystallisation of cor- dicrite, the reaction—chlorite ++ andalosite + quartz = cordierite + vapour (Sieferr & Schreyer 1970) seems to be consistent with the observed mineral assemblages, Based on the experimental P-T conditions for this reaction, and for the aluminosilicate stability as deter- mined by Holdaway (1971), the crystallisition of cordierite and andalusite in metasediments in the type section probably occurred at pres- sures below about 3 kb and al temperatures estimyted to be less than 540°C (Milnes un- pub. Ph.D. thesis) - Discussions and Conchusious As a result of our studies on the upper part of the type Kanmantoo Group, several facts emerge from which w nurnher of conclnsions can be drawn additional to those given in Dally & Milnes (197tay-. A. Srratigraphile Relationships In no instance throughout the whole of the coastal sections have we been unable to ascer- lain bedding. Transposition as described by Talbot & Hobbs (1968) is confined to the vicinity of Petrel Cove. Most outcrops retain their gross sedimentary features despite the Lec- tunis and metamorphism, This is readily dis- cernible from the accompanying fignres, 44 232 Vhere appears to be conformity between all the fermations muking up the Kanmantoo Group as sec out in Table 1. Phe validity ot thy straligtaphic scheme is enhanced by the oceur- reace of a virtually identical sequence on Dui- ley Peninsul, Kanguroo 1, (Daily & Milnes. I971b, 1972b}. As Our investigations on. this ishand ore as vet jacomplete there is still room for an upward continuation of the sequence beyond the Middleton Sandstone. The latter constitutes the youngest purl of the Kanmantoo Group in the Mt. Lofty Ranges, Lt is worth nog that in the original definition of the Kanmantoo Grolp, Sprigg & Campana (1953, p. 14) stated that “the upper boundary of the Kanmantoo Group remuins undefined”. B. The Kungarvoian Movements and Karrnan- too Group Sedimentation All the original sediments making up whe Brown Hill and Wattaberr) Sub-groups in ihe lype section were clastics which ranged in grin size From clay to pebbles ut least S em in dia- meter limestones were absent. Indeed. car bonate shows up only as pebbles in conglomer- ates or pehbly sandstones. However, its former presence as iin accessory is probubly indicated by epidote-rich bunds in the Midelleton Sand- sions innit ws the thin calc-silicate sesrecations and hands in all the other stratigraphic units within hath sub-groups, Metasandstone is by far the dominant lithology throughout most of the Kanmuntoo Group. The sands were essentially immature all contained vurying amounts of clay and silt Lmud) as matnx, Quartz and subordinate feld- spar were the dominant sand-sized particles ind were derived mainly from the older Precam- brian Urystulline basement, The rapidity of deposition may he giuged mo only ty the immaturity of the sunds but alsy trom the dominance of pirallel lamination within the metasandstones. We Interpret this type of bedding as a consequence of the high flow regime that prevailed through much of the depositional history of the group, Intervals with cross-bedding and especially current-ripple lamination are common sind represent deposi- tion at lower flow power as has been estub- lished by Simons ef al, (1965), Guy er al, (1966) and Williams (1967). Aflen (1970, Figs, + & 6), using some of these experimental data, hus shown the possible alternative sequences of sedimentary structures that may form for yarying graity size with decreasing flaw power at the time of depasiunn, ‘The sands were taid dowat by currents, which &. DAILY und A. R. MILNES over long periods of Lime were largely unidirec- tional, Measured current directions from sedi- ments infilling low amplitude scour-channels wihin the Brown Hill Sub-group indigule dis- (ribuiion of sediment by currents flowing generally from the NW quadrant. This is simi- far lo current directions established for the uoderlying Inman Hill Sub-group, We have been unable to detect a decrease in pebble size towsrds the east for conglomerutes in the Brown Hill Sub-group, though such aw varalion is discernible in the underlying Inman Jill Sub- group. For instance, conglomerates in an aver- turned sequence of metasandstones at Penne- shaw, Kangaroo T., contain clasts up to 30 cm in diameter. In correlative conglomerates in the uppermost parts of the Tapanappa Formution near “Tunkalilla Beach, the maximum pebble size is 7 cm. Uhe grealer distance of transport for these pebhles is jlso reflected in the lower proportion of carbonate clasts relative to other clast types, The persistence of lenticular conglomerates und pebble bunds into the upper levels of the Balquhidder Formation. indicates that the neat- hy tectonic fands, elevated in response to the Kingarooian Moyements, periodically contri. buted gravels to the basin (fur discussion on these movements sec Daily & Milnes 197 1a, p, 20). Evidence, mamly from Kangaroo L and Yorke Peninsula, indicates that the pebble suites were derived from the erosion of a strati- graphic Fy a Pe] Bilt Kho Stu a ESI Sor ea ’ Bie = o msl | ; mje E uw = o l< Ola zz _ al’ 2 es ae 2h 5 Tr wads =. a ee > a as > ge aa = pO A Ener Loe Roe ~ Ste pee 1 Nee 3) NATIONAL -"» yg SEE WOES fo oa <3. owe mh ee Fiz 1 STRUCTURAL GEOLOGY OF WARREN NATIONAL PARK LEGEND FOR LITHOLOGICAL MAP im =| Alluvium ( Brotite Zone Rocns. | Fine-qramed phyllites. dolomites, dolamihc phyllites, quartzites HvaNrte-ANDaLusITe ZONE Rocks Calc-silicate rocks (diopside, scapalita, amphibole), fine grained khrotted schist Fine-qrained Knotted schist, pyritie schist, quartzose schis! Pink felspathic quartzite horizon Tramotite rack with interbedded felspathic and actinolitic sandstone ] f acy Felspathic sandstone Siitimanite-Muscovite Zone Rocks = tg S. si ey O = Granite qnaiss (quartz-microcline- Plagicclase-bictite-muscovite gneisal Course-grained crumpled schist (kyanite; slaurolite, sillimanite) Tremolita rack horizon Felspathic sandstone with Fitanifercus haematite and muscavite ” BASEMENT Coarsé-qrained crumpled schist and Bad gneiss \siflimanife-muscovite zone} Tertiary deposils and minor intrusions nat -shown ee Inferred Fault re —— Inferred Thrust en Fault Mélange 1 Le Lenin ty ’ Se Felice J — Road or Tack ~ River or Watercourse * Mine or Prospect Gid Adapted From 1000yd. Military Grid System Fig. lL. (Opposite). Lithological map showing the distribution of the principul divisions of rock types in the region around rhe Warren Reservoir. 285 and the composition of this rock suggest an orginal marl. Pods and lenses of quartz and segregation pegmatites are also common in the outcrop. No attempt has been made 16 map litho- logical variations across the remainder of the inlier. although exposure is sulliciently good for this ta be a promising line of attack. Reconnaissance observations have not revealed a great deal of lithological variation. Almost all rocks appear to have had a pelitic or psammiopelitic ancestry, although there are some more quartzofelspathic varieties in the South Para downstream from the weir. The biotite-rich schists and amphibolites noted a1 the weir are to be found elsewhere as small! isolated. occurrences, but are apparently quite sparse. No rocks of the “Houghton diorite” type (Benson 1909) have been found in this inlier. The only rocks with an intrusive charac- ter are scattered quartz pods and dykes and abundant pegmatoidul rocks, mostly ot a segregation type but with rarer crosscutting varieties containing sparse beryl and tourmu- line. Amongst the pelitic and psammopelitic meisses compositional variations range from sillimanite (sericite)-rich gneisses (e.g. grid rets. 909082 and 916106), through varieties with less sillimanite, similar to the weir gneisses described above, to quartzofelspathic encisses lacking sillimanite. Some of the latter may contain abundant well-twinned microcline, Or puss mto rocks consisting almost entirely of muscovite und quartz, such as the coarse- grained crenulated schist immediately under- lying the melasandsione on the shore of the reservoir north of the weir. Within each com- positional group are a number of structural variants, such as folded, crenulated, lineated, banded, striped or granulose gneisses, depend- ing oo the Jocal structural history of each rock. A study of the metamorphic minerals and textures of the basement rocks has indicated that they were brought to a metamorphic temperature peak Jate in their structural his- tory. This metamorphic peak was apparently uniform over the whole inler and reached the stage where sillimanite was stable in the presence of muscovite in aluminous. schists, No evidence has been found for any extensive breakdown of muscovite and potash felspar (mictocline) is confined to the non-aluminous varieties. Of other index minerals, garnet and kyanite have been rarely recognised and anda- 236 lutsite aiid staurolite have not so far been identified, It seems that (he basement rocks have an apparently similar metamorphic his- tory to the Adelaidean schists and vneisses Immediately overlying the metasandstone unit, and it is helieved that the metamorphic peak indicated in the basement rocks was identical to that which may be deduced from tocks of the Adeluidean mantle. It seems clear that the pre-Adelaidean metamorphism of the base- ment rocks involved lower grade conditions thai those reached in the early Palaeozoic urageny which affected both basement and mantle. Spry (1951) reported a fall in grade from south to north, involving sillimanite, garnet and biotic zones, for the early pre-Ade¢laidean metmorphism of the nearby Houghton Inlier, which could be construed to fit the above conelusion, bul Talbot (1962)! has disputed this grade variation. Talbot (1963) has shown Ihat the Houghton Inlier has suffered three metamorphisins. ‘I'wo pre-Adelaidean episodes, the earlier involving upper amphibolite facies conditions, and the tater involving pervasive greenschist facies retrogression accompanying strong phyllonitisation, were averprinied by a ereenschist facies (biotite zone! episode accom- panying the Palacozoie metamorphism of the Adelaideun mantle. A tentative Rb-Sr date of 867-4492 my, has been suggested for the upper amphibolite facies. metamorphism (Couper & Compston 1971), while the Palaeo- Zoic metamorphism has heen daled al 490415 m.y. (White, Compston & Kiceman 1967). Jn the Warren Inlier the Palaeozoic meta- morphism has obscured all evidence of pre- Audelaidean metamorphic grade in the base- ment cocks. [| is conceivable that rocks of the Warren Inlicr have passed through « phyl- fonilic stage similar to the Houghton Inlier, bul there & so far no cvidence of at or of any earlier hivher grade metamorphic episodes, Che late metamorphic hiktery of the Warren Inljicr tocks and the overlving Ade laidewn schists is also similar, involving per- yasive retrogression of sillimanite to sericite and muscovite and uf biotite to chlorite, and she appearance of late strain features such as hent and kinked micas, lamellar twinning in plagieclase and deformation bands and lamel- la@ an quartz. K. J. MILLS THE LINCONFORMITY The actual surface of unconformily is only clewly exposed in two loeulities; on private Jand south of the reservoir (grid ref, 925108), and in the southern part of the Warren Nuwtional Park (grid refs, 909088-91 2090). The Warren National Park exposures ate the must instructive and will be described first. Several large exposures in the southern portion of the Warren National Park display a fingernail sharp unconformity surface, There is a large angular discordance between the gently south dipping quartzofelspathic banding in the basement gneisses and the near vertical hedding of the overlying metasatidstone (Fig. 3f). The basement gneisses; here ure coarse-grained, mica-tich and schistose. The preminent quartzofelspathi¢ bands may be related to original bedding, but are probably transposed and Iack stratigraphic significance. The basal units of the overlying metasandsione ure nich in muscovite and strongly schisiose. These unils become quite friable on weather- ing, resulting in a ntgative relief against the more massive basement gneisses, A basal con- vlomerate is develuped locally at grid ret. 911088. The pebbles range up ro 30 cor in length, aré moderately angular and are locally derived from the quartzofelspathic bands of the underlying basement. The bed is up to half a nietre thick and i observed to he welded onto the basement. In adjacent out- crops the conglomerate is absent and # musco- vite-vich schistose metasandstonc. characterised by an unusual abundance of haematite ind ou few scattered rounded quartz of quartzite pebbies. to a few centimetres in diameter, is welded directly on to the basement with a sharply defined contact. A strong metamorphic and situctural convergence of the basement and the overlying Adelaidcan beds has ob- scured ihis camlact in some exposures. Where the contact is clear the unconformity surface is seen to he quite irregular in detail, with harder bands in the basement protruding into the basal beds. A metre or so above the unconformity the bedding in the metasaned- alone is unallected by these irregularitics. Following the inlier boundary to the sauth- west from the above localities, no actual exposiires of the unconformity were seen, although a boundary between the basement ! Talbot SLL. (1962)—A study of the structural and metamorphic relationships between older and younger Precambrian rocks in the Mr. Lofty Rauge Olary Are; South Australia, Univ, Adelaide, Ph.D, Thesis. STRUCTURAL GEOLOGY OF WARREN NATIONAL PARK encisses and the metasandslone can be mapped, the basal metasanudstone exposures being agam enriched jn hacmatilc, In the south-west corner Of the inher the boundary begins to turn castwards aod disappears beneath alluvium. Apart from one smul! ex- posure of cross-bedded hucmatite-rich micta- sandstone overlying the basement a little further castwards, no other exposures of the contact are seen, the southern ind eastern sides of the inlicr being delincuted by a major thrust fault. Following the inlier boundary to the north- enst from the Warren National Park expo- Sures, the basal metasandstane beds are haematite and muscovite-rich, but no actual unconformity surface was observed. ‘lhe actual contact lies near the base of a sleep escarp- ment of husement gneisses. This escarpment is related to the friability of the basal beds of the Adeluidean sequence and the erosional Teststance of the basement gneisses. Rainfall tun-off trom the basement genciss exposures engenders a thick undergrowth near the comlact, On a track extending porth-west of Lookout Tower Hill (grid ref. 918105) a haematite-rich quartz-museayvite rock is seen close to the inlier contact as Ihe lowest bed in the meta- sindstone sequence. This rock is composed of 65% quartz as large grattoblasis to 3 mim, 25% muscovite, 10% haematite, and 5% barite. as evenly distributed interstitial grains. Much post-crystalline sttuin ts evident in the quartz and muscovite. Following the inlier boundary westwards around several folds, no actual exposures of the unconformity surface were found. The basal beds of the Adelaidean are muscovite- rich metasandstones, usually bearing notable hucmalile or a trace of biotite, Bedding is out- lined by yuartz-rich bunds, und occasional Tounded quartz or quartzite pebbles to 3 cm in diameter are scattered along some bedding planes, The adjacent bastment is mostly a inieu-rich schist, No unconformity surface was observed along the long meridjanal western contact of the inher although the boundary can be closely mapped. Again muscovite-rich schistose metasindstones are churactenstic al ihe basal beds, On the Engineering and Water Supply access road (grid tef. 902125) a two metre gap of soil and prass separates whit appears lo be the basal bed, a coarse hacma- lite-rich quartz-muscovite metasandstone with & few small pebbles, from strongly folded 287 coarse-grained quarlz-lelspar-bidtile-muscayile gneisses of ibe basement. Th haematite-ch bed can be seen at several points further nor h hear the inlier contact, but nearer the porthem tip ef the inter this basal bed has apparently lensed out and beds of muscovite-rich meta- sandstone [rom slightly higher in the sequence come to rest on the basement. From the northern tip of the inticr (Hale National Park) to the reservoir the inlier contact was nat eusily mapped. The unconformity exposure described by Hossteld (1935, p. 37) could not be found, although bath busement and meta- sandstone rocks ure sufficiently well exposed near the E. & W.S, access road north of the weir to place the inlier contact on the map with confidence. South-east of the weir the fnlier boundary becomes involved in several tight folds—in part interpreted previously as ua cross-fauh (Mills 1963). On the ridge west of Wirrianda homestead some good exposures of the un- conformity surface may again be seen. Here a coarse-grained muscovite and hacmatite-rich schistose metusandstone overlies a chosely folded mumuscovite-rich gneiss containing quarizofelspathic layers and some haematite. The unconformity surface is again seen to be irregular in detail, Scattered pebble-like quartz pods to 10cm in diameter occur in both the basement and metasandstone and are ap- parently of segregation ongin. Immediately south of the homestead the haematite-rich basal beds of the metasandstone run into the Wirrlanda Thrust which marks the eastern boundary of the inlier. In conclusion, an unconformity between rocks of the Warrea Inlier and the overlying Adelaidean sequence is well established, The inlier boundary can be mapped alung most of its length with confidence, and details of the actual unconformity surface can be observed at two localities. The Jowest beds of ihe Ade- laidean sequence are composed of schistase muscovite-bearing nmvetasandstanes and the basal beds are usually enriched in haematite, although not as enriched as in ihe ML Bes- semer sequence on ihe eastern side of the neatby Houghton Intier (Miles 1950) A basil conglomerate of the Jocal derivation has been found wt onky one loewlity. THE ADELAIDEAN SROURNCE The siltimanite-muscovite zone The lowermost units of the Adelaidean sequence overlying the basement of the Warren Inlier have reached the grade of meta- 188 morphism where sillimanite and muscovite are in stable equilibrinm in rocks of appropriate composition, Vhe basul formation is a thick brows-hedded = achistose = felspathic metasand- stone, which is overlain by a thick aluminous peli Formution, “The top of this pelilic formation has been cul out by mayor Caults which have brought the sillimanite-muscovite zone rocks into conjunction with tower grade sequences. Three distinet phases of strong compressive deformation have alfected racks in the silimanite-muscovite yone and no re- liable estimates of stratigraphic thicknesses can be made. The lithological character of the basal meta- sandstone formation in Ihis arca has been carefully described by Howechin (1906, p. 255; 1926, p, 5) whe noted its cluse similarity to the Aldgate Sandstone, The mectusandstone supports rather sparse vegetation and usually forms large lcucoeratic outcrops. ‘Vhe friable nature of this rock preserves the freestone tchatacter of the Aldgate Sandstone despiic high vrade melimurphism, Bedding, cross- bedding and festoon-bedding, outlined by laminoe of titaniferous haematite, are beauli+ fully) preserved although considerably ap- pressed by subsequent tectonic deformation. The haematite laminae ate normally about one millimetre in thickness, but rare layers up to 10cm in thickness huve been observed, Miles (1950) presents the results of a chemical analysis of the ulaniferous haematite from at specimen collccted in the northwest corner of this area, In some oulcrops (eg, grid ref. 908070) the metasandstone is strongly mag- nec; Magnetite presumably replacing the hae- mate us the principal opaque accessory, H is not known whether this magnetic propery is confined to certain beds. As described in the previous section, the lowes beds against the unconformity are nor- mally enriched in haematite, this component being scattered evenly throaghout. These hae- matite-tich beds are not mare thin a Tew metres in thickness aid in roahy places they thin ovt and disappear entirely, The next 30-50) tnetres of section consisls of a museo- Vite-enriched metasandstone, perhaps best desccibed os a quatlvamuscovite schist, The remainder of the sectiun, perhaps amounting ty SOO metres, consists of Selsputhig metasand- stone, characterised by titaniferous hacmatite Inminae outlining the bedding surfaces, with lutenmitrent imuscoviteenriched layers. The base of this mere qulittzofelspathic section K. J. MILLS was taken as the base of the psammutic forma- tion oo my eurlier map (Mills 1963). As desevibed by Howchin, rounded pebbles up Lo 30em in diameter, mostly of quartz or fine- graihed gqualtzite. ace distributed throughout the sequence, ullhough more commonly eo- countered at certuin horizons, True conglo- meratic beds are rarely observed, the pebbles being mostly scattered unevenly on bedding surfaces throughout the outerop. In some exposures the pebbles are sten to have suffered a strong flatlening and some elongation result- ing From tectonism. Stratigraphic bedding can usually be identified and opportunities for facing observations based on cross-bedding are numerous. Some slicing and transpasiiin of bedding has heen woticed in the muscovite- enriched section near the base of the stqtience in. the South Para Gorge, Occasional pegmi- tite and milky quartz veins carrying accessory ilmenite plates Intrude the metasandstone throughout the area. Sixteen specimens covering the composition range of the psammites were examined micro- scopically. Quartz, ranging from 25-75%, occurs in some rocks os Jarge strained clasts up to 3mm. while other suniples, particularly the qwore micaceous ones, demonstrate all slages in the recrystallisution of original strained clasts to new metamorphic grano blasts. This recrystallisxtion is closely nsso- ciated with the axial surface schistosily of the second compressive deformation. In some samples the new quartz grains preserve a pro- nounced preferred orientation of their c-axes, wppurently related to the second delormatiun. Sume quartz clasis are sagenilic. Potash felspar (0-30% } is the sule felspar component. It usually occurs ax strained tartan-twinned cfists up to 2 mm. In some specimens the clasts are apparently untwinned but have partially re- crystallised to small well-twinned pranoblasts near their margins, Muscovite (S-50%) is pre- sent in all specimens, usually as large flakes vp to 2mm, commonly showing late strain effects. It appears to be wholly of meta- morphic origin and is. responsible for the pre- servation of many of the tecionicully imposed features of these rocks. Biotite is present in many simples up to 5% and is usually pleo- ehraic olive brown to pale lemon. Opaque grains (1-10%) are invariably present. Apatite, Zircon, monazite and tourmaline, pleochroic pale pink to olive green, are accessories. Con- sidering the coarse-grained micateous Entisses above and below the schistose sandstones, the STRUCTURAL GEGLOGY OF WARRTIN NATIONAL PARK preservation of quartz and felspar clasts at this metamorphic grade is quite remarkable and the weakly metamerphosed appearance of the more quartzofelspathic varieties of this metasandstone miist be partly attributable to the preservation of these clastic features, The upper contact of the metasandstone ligains! the overiying sillimanite bearing pelitic schists is shaeply defined. In the south a thin intermitient tremolite rock bed, aormally ex- pressed at the surface as an opaline replace- ment rock, tharks the cantact, while in the east sume pelitic sehist is inserted between his bed and the metusandstone, In the north-west a sliver of coarse-grained sillimanite bearing pélitic schist is observed to rest directy on the schistese sandstone, The frue nature of the tremolitie marker bed can be observed in debris from a shaft sunk on the ridge nor.h of Sailors Gully where the rock below the weathered profile is composed of interlocking pale-green trenalite-actinolite prisms, Else- where the surface expression m an opuline ohaleeduny showing tremolite casts and some lale. Vhe thick pelitic formation above this tre- molite bed has been previously described in some detail (Mills 1963, p. 171) These rocks have auiicred intense folding and compression and true bedding cannot be recognised with cerluinty.. Although apparently quite thick, a0 estimites oO! straugraphic thickness can be made. The socks are coarse-grained micucenus schasts.ind gneisses, usually displaying alumino- sificnte knots, tross-cutting crenulatiens and small folds in their schistusity, leading to the field name “crumpled schists” (c.g. Miles 1950), ‘The major primary constituents are quarty, plagiaclase (An 0-15), biotite and muscovile with variable amounts of sillimanite and kyanile and rarer staurolite and garact. Assemblages of these imtinerals developed in rocks of appropriate pelitic composition and approached equilibrium’ in a sillimanite- Inuscovite grade metamorphic peak during the second deformation, As wilh the basement encisses, HO Metasomatism is considered to be necessary for their formation. A pervasive retrogression, which took place in the inier- Kinematic periad between the second and third compressive events, has resulted in the extensive alteration of aluminosilicute minerals and biotite to sericrte and chlorite. This retro- gression is more pronounced in some zones where shearing associated with thrust move- muuts is belicved to have been important. 289 Some introduction of H.O may have secom- panied this tetrogression, fia the eust, part Of the pelitic formation has been replaced by a hody of granite gneiss, as pieviously described in greater detail (Mills 1963}. Although the chemical processes which led to the formation of this granite gneiss are hot yet understood, extensive chemical migra- tions are not envisdged in its formation. This eranite gneiss and its immediate envelope of schists have escuped retrogressioa, Ti is en- visaged that the granite gneiss body behaved as @ sohd impermeable block durmg the reire sressive cpisode which affected the adjacent schists, In Conclusion, the hasal metasandstones and the woverlying pelitic schists have been sub- jected lu a metamorphic peak in the middle amphibolite facies under temperature condi- lions where sillimanite was in equilibrium with muscovite. Some clastic textures have been preserved in the more quartvofelspathic meta- sandstone beds but in the pelitic schisis exter sive recrystallisution took place, Sillimanite, kvanite, Staurolite and garnel were crystallised during this. metamorphism aod grannisation occurred Jogally, At a liter sige under yreen- schist facies conditions. extensive relroyression took phive in the pelitic schists. The kyanite-andalusite 2one A sequence of Adelaidean rocks belonging to the lower amphibolite facies have been (aulled against rocks ol the sillimunite-musco- vite zone in the south, cast and north-west. North of the Warren Reservoir, Alderman (1942) placed these rocks in the bjotite zone, a reasonable supposition considenng the abun- dance of biotite-quartz-felspar schists which oceur in this sequence. Aluminuus beds con- taining undalusile or kyanite Knots are rare and these koots are usually severely relro- gressed jo sericite, Cale-silicaie beds in the seqttence carry diopside, scapolite, amphibole, epidote and oligoclase-undesine, confirming their amphibolite facics character. This se- quence of rocks is characterised in the field by the fing to medium grain-size of the pelitic and psammopelitic umnils and their stmple structural character dominaicd by a single schistosity, which in most outcrops is parallel or nearly parallel to well-defined bedding planes and bedding laminations. Crenulations in this schistosity are rarely found, and if present are weakly developed. The sequence ¢ast of STRUCTURAL __MAP OF THE WARREN NATIONAL PARK AND WESTERN POATION OF THE MT CRAWFORD STATE FOREST O00 ine Yet UKAPRAINGA Mine | = ir 9 = “ Zz e r # Boe ee o-_ = Le z — RUST ASS peek?) fl = aa i 28 rae I aN ey r vA s “ —= STRUCTURAL GEOLOGY OF WARREN NATIONAI. PARK 291 LEGEND FOR STRUCTURAL MAP Lithological contacts _ oo a ad Trends of bedding surfaces 7 Unconformity ae Marker ‘horizons Stratigraphic facing = we -es tablished —_—_—~ Foults ~inferred -inferred are Thrusts -established aa Fault mélange ress ADELAIDE SUPERGROUP BEDDING eS = * Sq Inclined Vertical Horizontal Inverted FIRST DEFORMATION \ Si, %, 5, LiBlg* Ls, SECOND DEFORMATION Sz 4, 52 S, LIBIg? \LIB)e? THIRD DEFORMATION % Sa S. Sa Sy Xk LiBles Bg? L(B)e? \ BASEMENT Compositional layering » Schistosity * Axial surface to folds in schistosity “s Lineation in schistosity ™ Hinge lines of folds in schistosity Fig. 2. (Opposite). Structural map showing the principal structural features. in the region around the Warren Reservoir. the granite gneiss has been briefly described (Mills 1963, p, 171). Exposure of this sequence is very poor iin the south and south-cast bul it seems that the lowest unit is a pink meta-arkose containing sorne haematite laminac, but no mica, and preserving good clastic churaclers, South of Watts Gully this meta-arkose is overlain by a sequence of fine to medium-grained quartz- felspar-biotite schists containing some pink microcline-rich meta-arkose beds with acces- sory pyrite. Then follows a tremolite rock marker unit, expressed at the surface asa ten metre width of opaline replacement rock. This unit has been traced intermittently, using exposures. of opaline replacement rock or talc, around to the eastern side of the granite gneiss where it forms a thick and useful marker horizon. At the surface it is usually expressed as opaline chalcedony, but fresh samples from below the weathering profile consist of coarse interlocking tremolite prisms. North of the present area this same horizon is apparently represented as a tremolite marble and has been traced from well north of Williamstown to. the proximity of the Warren Reservoir (Howchin }926, pp. 7-8; Hossfeld 1935). East of the pranite gneiss the tremolitic marker unit is overlain by a mica:schist group consisting of fine to medium-grained quartz- felspar-biotite-muscovite schists with thin inter- bedded meta-arkoses, Most of these meta- arkoses are fine-grained, pyritic, graphitic and very enriched in microcline. A useful pink Sels- pathic quartzite marker horizon crops out persistently a little above the tremolitic marker unit. Some mica schist beds contain small knots which have altered to fine sericite. Rare kyanile relics have been found in these knols. The uppermost part of the sequence examined is a Calc-silicale group consisling of inter- bedded fine to coarse cale-silicate rocks and knotted fine-grained mica schists. A wedge of rocks belonging to the kyunite- andalusite zone has been mapped west of the Ukuparinga Copper Mine, in the north-west corner of the area. The lowest bed here is a thick medium-grained dolomitic marble, which may be equivalent to the tremolitic marker bed east of the granite gneiss. Specimens of this rock consist largely of dolomite with variable amounts of tremolite, talc, muscovite and primary chlorite. Calcite is rare or ubsent- ‘Two. analyses of this marble are presented by Miles (1950), This marble is overluin by a mica schist sequence, containing fine-grained 242 K. F. MILIS pyritic meta-arkose beds, very similar to that east of the granite gneiss. Higher in the sequence some mica schists have sericite knots containing andalusite relics. The cale-silicate group has not been recoguised here, although a second marble unit crops out high ia the sequence against the Williamsiown-Mecudows fault. Biotite zone No attempt has been made te map beds in the low grade sequence expasedl west of [he Williamstown-Meadows fault. Near the [fault the main rock types are fine-grained grey dolomites, grey-brown dolomitic phyllites, phyilitvys and fine-grained quartzofeispathic pyritic metusiltstones. Rocks of the biotite zone sre usually extremely fine-grained (0.01-0.03 mm). A pale mustard-brown weakly pleachraic biotite is characteristic of the phyl- litic tocks. Dolomite seems to dominate over calcite in’ the carbonate rocks. A thick sequence of grey impure dolomite; (20% quartz, plagioclase, muscovite and opaque impurities) is exposed south af the South Para River CONCLUSIONS ‘The basement rocks of the Warren Inlier are Wnvenformably overlain by the Adelardean rocks. The Adelaidean sequence is divided into three portions belonging to different mela morphic and structural levels by several major fault surfaces, The basal sillimanite-muscovite zone rocks and the kyanite-andalusite zone tocks of the Adelaidean sequence are sepu- rated in this. area by Faults which ate surfaces of marked metamorphic and structural di- continuity. It therefore seems likely that there is a large stratigraphic gap between the Sequences represented within these meta- morphic zones, Further detailed mapping, par- ticularly to the north of the present area, may help to determine how much of the struti- graphic sequence has been removed. Until this problem is solved it seems unwise to attempt correlations of individual beds or parts of the sequetice with other beds or sequences in the Mt. Lofty Ranges. The Williamstown- Meadows fautt brings biotite zone rocks in the west against sillimanite-muscovite zoue rocks. As suggested by Miles (1950) the biotite zone tocks probably belong to a much higher stratigraphic and metunwrphic level in the Adelaidean sequence and displacernent on this faull must be very large. Structural Relationships between Mapped Lithalogical Units PRELIMINARY COMMENTS Three successive compressive deformation events, Fi, Fe and Fs, have affected the Ade- Juidean sequence in the vicinity of the Warren Reservoir and the structural features produced in these de‘ormative phases will now be described more fully. Metamorphism of the Adelaidean sequence began betore or during Fy and reached a peak temperature in the amphibolite facies early in the Fy episode. A series of east to west thrust movements occurred Jale in the F, event and extensive Telrogression under greenschist facies condi- fens accompanied or followed these moye- ments. ‘Uhe thrust sheets were folded during g Tather hrittle low temperature F, event. After F, and late in the cooling history the Williams- town-Meadows fault developed its maximum displucement, In describing the struelural features and events in the Adglaidean scquence it is cane yenient to introduce the following shorthand nojatian? (see also map legend, Fig. 2)—- S) —surface of compositional layering relating to pri- maty bedding. F,, Fu, F, --the three successive compressive events. S,- Su. Sp —axial surlaces to fulds produced in the F,, Fa, F; events respectively. —fSulds in bedding with 8. as axial surface etc. —lineations resulting from Sp-Sy intersections etc, —strain elongation axis in Sy ete. Orientation measureinents are recorded in telation to true north-point azimuth. Figures 2 and § illustrate the principal structural features B(Sp-So) ele, L(Sy-So) ete, LiS,) ete. THE BASEMENT (WARREN INLIER) At the type locality of the basement rocks at the Warren Reservoir Weir a partial history of tectonic events may be dcicrmined. As in all exposures of the basement rocks, bedding 2 Owing 10 ptinting difliculties this form ef notation is adopted im the cext cather than ths more conventional form shown on the map Jegend. STRUCTURAL GEOLOGY OF WARREN NATIONAL PARK with stratigraphic Significance cannor be proved, although quartzofelspathic bands and layered lithological Variations may reHect 4 primary bedding precursor. Lithological layers and schistosities in Ihe expusures near the weir are strongly folded on all scales and at first sight the folding appears to be rather regular wilh a prominent schistosity. defined by course mica plates, crenulated and folded about shallow plunging axcs (Mills 1963). This schistosily is observed in detail to be a highly evolved crenulation cleavage, and is therefore an axial surface schistosity belonging io at least a second deformation event. In paris of this exposure this schistosity has been folded into recumbenr Z-shaped folds with near hori- zontal hinge surfaces, and these folds have been overprinied in turn by a widespread later folding with a moderately west-dipping axial sutfuce, produging ¢renulations in the earlicr schistosuy with ow wavg¢lengih of O,5-3 cm, Thus, at least four overprinted fold even's can be distinguished in this exposiire, and there are yet other folds present which may represent a lifth deformation. The earlier faleds in the weir exposure tend to huve a. ptygmatic style in which the fold hinge lines have a more regular orientation than the hinge surlaces, Nevertheless, the hinge lines remain curvi- linear on all scales and the folds are never strictly eylindrical, The Jater folds are also irregular and often of polyclinal siyic, this being puriistly induced by the presence of many large intrusions of pegmatite and blocks and lenses of quurtzolelspathic gneiss which have acted as. buffers inducing inhomogeneous strain during the later fold movements (Fig, 3b, c, e). Due to these irregularities, reliable field? measurements of the orientulion of siruc- tural elements are difficult to make, even in the most favorable exposures. Lisewhere in the inlier most exposures show signs of complex folding and overprinted de- formation structures, justifying field names such as crenulated or crumpled schists. Bedding cannol be veriligd and any lithological layering present is strongly lenticular und suggestive of Irunsposition processes, Sone exposures are very irregularly deformed and tio orientation measurements can be made, but some of the more micaceous schists display fairly regular folding of their schistosity, approaching local cylindricity, There ts much variation in the style of small folds from concentric to shar} chevron folded forms (Fig. 3a. dc. fi). Most pegmatite intrusions have alse been folded 243 along with the host rock schistosnies. Examination of exposures in the vicinity of Lookout Tower Hill agam suggests multiple deformation involving at tcast four conipres- sive eVents, the Jutest phase involving ubi« quitous tight to ope chevron style folds in the earlier schistosily of the more micuccous rocks. Microscopically the basement socks are cuoumegrained, wilh a prominent schistosity defined by oriented mica flakes, which are oflen segregated into Jensoidal gneissic layers with signa of evolution thtaugh an earlier crenulation cleavage stage. In parts of the inlier a strong mineral fineafion, detined by sillimanite fibres in aluminous schists or mic plate dimensions, 18 observed within the Se SUB- a, * LB)! a S, LiBIee a Ss AREA L(B) 3? * xe ‘Sh Sz 35, pot i L(Big! | 64 Sz 2 L(ahge F2-072) Rq 34 LIB)SS (MAX GO-O701 42 L. / ; R { | A ae 25 Lip) Ss 33 LBS : (Max. ¢5- 058) z 72S, 172 3; (MAK (wax, fa— 2a) Ro te a 2 109 .(B)$ | \MaAwe at 's L Fig. 7. Lower hemisphere equal area projections of structural elements measured in coatse-grained Adelaidean schists of sub-arca RK. True north at top of diagrams, Contours at 0.5, 5, 10, 20. 30% per 1% area. STRUCTURAL GEOLOGY OF WARREN NATIONAL porphyroblasts jo relation to matrix grain size indicates gerowlh during and after the F, Ueformation event. In other rocks ellipsoidal quartz, felspar and carbonate crystals, and the Jong axes of amphibole prisms, may define S,. A moderale quartz c-axis fabric has been noted im some specimens of quartzofelspathic schist and ay early quartz veinlet cutting the S, surface of a quartz-felspar rich schist in the north-west block was observed to be recrystal- lised and to have uw strong quartz fabric in which most c-axes were aligned within the S, surtace, A fait to strong mineral streaking lineation is notable within the S, surfaces cof some exposures. This lineation is defined by elongate mica plates and porphyroblastic knots in schists and by amphibole. prisms in calcareous rocks. A set of cross joints is commonly scen lo lic perpendicular to this lineation. In the mica schists the lineation. is defined by a ¢om- binalion of two cllects, Firstly the mica plates are up to twi¢e as wide parallel to (001) in the direction of the lineation than they are across it, the biotite plates being considerably more stumpy in form than assoctated musco- vite plates. Secondly the mica plates 2re much more diversely oricnted in sections cut per- pendicular to the lineation than they are in sections cut parallel to it: that is, the mica plates are fautozonally arranged about the lineation axis. In the absence of suitable strain markers in the present arca it is not possible to determine whether this lineation as due to the mimetic growth of crystals in lines of bedding- cleavage mtersection, L{S,-S;}, of is a tectome strain lineation, L(S,), developed during meta- morphic mineral growth, The penetrative nature of this lineation in many cocks, and strain shadow ejfects around syntectonic por- phyroblasts, favours the latter. No mesoscopic B(Sy+S,) folds have been observed, In sone schists in the north-west block o mild crenulation in the S$, surface, showing syntectonic crystallisation of the mica plates in the crenulation hinges, suggests effects of the F, event. Some mesoscopic F. folds of hand specimen size have been found as Aoat in the north-west block, but they are apparently quite rare. These folds show §,, parallel to 8, folded into V-shaped sivles with planar limbs, well defined hinge regions wad thickened noses. Likewise the effects of the Fy, event are weakly developed in this sequence, The PARK 3s Gumeracha Goldfields antiform in the south- east has macroscopically flexed the 8, and 8, surfaces, but otherwise, only aecusional bax- like post-crystalline c¢renulatians, showing strong strain effects in the minerals of their hinge regions, are considered to belong to the F.. event. Biatite zone West of the Williamstown-Meadows fault line fine-grained impure dolomites, dolomitic phyllites, phyllites and phyllitic slates bhelong- ing to the biotite zone are also characterised by multiple defarmation, Evidence for ihree overprinted deformation phases can be recog- nised in some exposures and provisionally equated wath the B,, Fy and Fy events. These rocks have a very fine grain size, quartz and micas averaging 0.01-0.015 mm, and invari- ably have a strong §; slaty cleavage labric defined by the shapes of curbonate grains and the parallel orientation of muscovite and bio- lite plates. "Strain shadows" are presence around some opaque minerals, The ¢c-axes of quurle grains possess a strong orientation in the S, fabric of some phyllites, with most c-uses tending to Te im the S, surface. S; is seen to lie at large angles to S, in some exposures and broad hinge regions of B(S,-5,) folds are present. So is usually well defined by compositional layering or Jaimination. At 890120 well developed finely spaced strain-slip or crenulation cleavage, Sy. was observed in phyllite. Microlithons between the crenulation cleavage planes. are about 0.3 mm in width. The S, cleavage within the micro- lithons as bent into the S, crenulation cleavage surfaces and this process ts ackompanied by unm increase i mica content within the Sy, surfaces. Apparent displacement on the S, sur- faces crossing the phyllite is not represented as displacement in cross-cutting quartz vein+ lets, but as. sharp monoclinal folds with atienuated limbs crossing the S. surface, Where S, is developed, mesoscopic 8(S)-S.) folds are observed in the bedding (Fig. 4h). QQuartzose layers are buckle folded, while car- bonate-rich laminated phyllite layers are strain slipped. ‘The folds are disharmonic on all ecales, but the So surtuces tend to have 4 consant orientation. Thin quartz stringers were seen to have been ptygmatically folded un a microsenpte scule in the Fy event. Later more brittle Kink folds are rarely observed and might be attributable to a weak Fy event. Oe FAULY SPRUCTURES Thrust faults Several thrust sheets have been mapped in (he present area on the basis of metamorphic and structural discontinuities. Vhese thrust sheets Wert emplaced during or after the Fy event and were subsequently folded in the F, eveot. Four principal thrusts are named. The Wirriynda “Uhrust, passing near “Wirrianda’ homestead situated on the southern shore of the reservoir; the Watts Gully Thrust, passing close to the site of the richest gold discoveries in the Gumeracha Goldfields; the Sanctuary Vhrust, largely confined to the flora and fauna sanctuary in the south-west; and the Murray Vale Vhrust, named after the pastoral property south-east of the headquarters of the Mount Crawtord Stule Forest. The Jast three named faulis appear to be hinged near the southern margin of the mupped area. The opalised Iremolitic rock bed at the contact of the mictasandstone and the course-grained schist sequence has proved to be a useful marker horizon in the identification of sequence repe- tiliom in the thrust sheets, There are no proven natural expasures of the thrust Fault surfaces in the area, and critical thrust shyet interplay, particularly in the south-west. ig obscured by alluvium and poor ouicrop, There is some evidence From the study of the mesascopic orientation data that the higher sheets rotated clockwise oVer the lower sheets in the south- west corner of the area. This may be the result of rotation during the thrusting move- ments or differential rotation of the sheets in the subsequent F, event. Numerous exposures of sheared and mylonitic gneisses in the thick pelitic seyuenve are thought Io have been deve- loped during the thrusting movements, On the northern slopes af the reservoir the Wirrianda Thrust is marked by a sharp contact between metasandstone and course- grained micaceous eneisses. South of the reservoir the sandstone cuts out and the hase- ment gneisses are brought into contact with the schists and gneisses of the Adelaitlean sequence, Although exposure is fairly good here. similaritics between rock types and the overprinting of mesoscupic Fy folds From the Adelaidean schists into the basement racks have obscured the actual fault surface, Further south the upper section of the metasandstone \nit reappears. but the fault zone is everywhere obscured by soil cover, North of Watts Gully (he fault line follaws the bottom of a steep Veshuped valley and its actual path across the K. J, MILLS mctasandstone further ta the south-west has not been identified. but it is assuined to eventually rin mto the Willramstowm-Meadows Paull. Structural evidence jin support of the Wutts Gully ‘Thrust is obtained from an area of woderate exposure near the centre of the patch of virgin scrubland of the flora and fauna reserve south-west of Dead Horse Gully, Here considerable discordance exists between structures on either side of the mapped fault trace, and 4 narrow splinter of pebbly micaccous mctasandstone appeurs ta lic within the fault zone, The Watts Gully Thrust is also responsible for a repetition of the strati- graphic sequence, Near Watts Gully the fault trace can be followed us 4 junction between schists and metasandstone and js marked in places by a distinctive white albite rich rock, which may carry tale or actinolite crystals. Under the microscope this rack is largely cam- posed of well-crystallised untwinned plagioclase with a composition near pure albite, carrying occasional rutile inclusions, Some interstitial quartz grains with slightly undulase extinction are dispersed through the albite, Scattered muscovite plates, preserving & microstructure like that of Sy in the pelitic schists, ure strongly bent and are encased or adjoined by the unstrained post-tectonic albite. The Sanctuary Thrust is of limited extent and is defined on the basis of a repetition of & belt of metasandstone shove pelitic schists, The fault trace is also marked in a few places by a peculiar white albilte rich rock similar to that described above, Movements on the Murray Vale Thrust were of greater magnitude than those on the underlying thrusts and resulted in the conjoin- ing of racks of markedly differing metamorphic and structural character, as described in previous sections, Fxposures of rocks near the thrust surface are very rare, and for most of ils length the thrust line is marked by a conspicuous strip of soil cover. In the field the position of the thrust has been placed on the basis of the readily mapped distinction between the coarsely crystalline rocks of the sillimaniteanuscovité zone and the medium cto fine-grained schists of the andabusite-kyanite zone. Much of the eastern margin of the granite gneiss has been reinlerpreted as the thrust surface. The banks of a road cutting on the improved section of the mitin road south of the reservoir, about half a kilometre north of the headquarters of the Mt Crawford STRUCTURAL GEOLOGY OF WARREN NATIONAL PARK Stale Forest, expose rocks on either sid¢ of the Murray Vale Thrust, Fine-grained schists and the thick opalised tremolite rock bed lit in conjunction with weathered amphibohle wand coarse-grained mica schists with intrusions. af pegmatite, The faulted contact is marked by & Narrow zone of green clay-like pug. The Murray Vale fault linc has been super- ficially traced north of the reservoir where it is marked in a few places by a sugury while albite rock containing green actinolilic spots. After passing through a left-handed displace- ment, probably a large F, fold, it traverses the centre of the large quarry excavated for clay und sillimanite. Near the base of the quarry the fault zone is seen to be less than half a metre in width and filled with pale greenish clay-like pug. The fault surface dips easterly at about 70° with some irregularities caused by open Fy folds, On either side of the faull extensive shearing, especially in the higher grade rocks to the west, has resulied in the formatiin of the unique Williamstown damourite schists containing kyanite uni corundum, massive sillimanite pods and clay Uepusits. The clay Ueposits seem to be related to Inte stage alleration within the faule zune. Wesl of the fault ale a variety of high grade poeises Showing Jess allteralion to clay away from the fault surface. Fine-grained lower grade schists are exposed cast of the fault. Same are very fine-grained pyritic schists which are extensively altered to clay near the fault, although still preserving Hresh pyrite cubes near the base of the quarry. Some open fokis, presumably of the F,, event, are visible in the lower grade rocks. North of the quarry the Murray Yale Thrust probably passes through another lurge F., fold resulting in the uppearance of fine-grained quartz-felspar- biotite schists displaying open shallow north- phinging F, foldy in small quarrics north of the forked junction of the rounds Jeading to “Spritigheld"’ and the Australian Industrial Minerals quarry. The Ukeaparinga Fault The Ukaparinga copper prospect in the north-west corner of the area is situated within the brecciated zone of a major meta- morphic and structural discordance, herein named the Ukaparinga Fault, Displacement on this structure must be at least as great as thot on the Murray Viele Thovist, but it is ancertain as to whether this faull should be grouped with the pre-Fy thrusts or i a brauch of the V7 nearby post-F, Williamstown-Meadows Fault, which it joins a little south of the South Para River, A fillle 19 the west of the Ukaputinga Fault, # parallel fault line has been traced on ihe grownd in an area of moderale exposure of the sehisty of the kyunite-andalusite zone sequence, but its importance as a fault struc: lure has not been determined. The Williamstawn-Meadows Fault An important fault line, separating fine- grained biotite zone rocks from coarse-grained amphibulile fucies rocks, can be traced in a north-south direction on the western side of the area, In eurlier literature this fault his been referced to as the Kitchener Fault, but as it appears that this name is based on a misconception, and since the author has been able to follow the path of this fault as a con- tinuous line from well north of Williamstown to well south of Meadows, the name Williams- town-Meadows Fault is preferred, Within the present area the actual fault zone, along most of its length, appears to be very narrow and sbhurply defined, although some exposures of tectonically emplaced foreign biogks lying within the fault zone fave heen shown on the map as fault melange. Where the fault line crosses deeply incised valleys, a sleep easterly dip of about 60-70" has been estimated for the fault surface at several points. ‘This would suggest that the fault is of the steep reverse Lype, bul unlike the thrusts described earlier, movement occurred after the F, folding episade, A uarrow zone of brecetated phyllite marks the fault zone al ong exposure north of the South Para River. South of the river fine- grained dolomites are brought against the fault surface im several places and close to the fault these rocks have been recrystallised to medium-grained white dolomilic marbles can- taining large plates of muscovite and talc and minor amounts of quartz and felspar grano- blusis and an opaque accessory, The ¢equi- granular hornfelsic texture and the partially dissolved nature of twin relics within the carbonates suggesis That these marbles were uffected by some form of contact metamar- phism, It seems that the higher grade hanging wall block was still sufficiently warm during and after the fault displacement to contact metamorphose the impure dolomites near the inmediate contact with the fault surface. In the south-western corner of the Warren National Park float and outcrop of felspathic Is and micacedus schists and gneisses of foreipn texiural appearance, opalised tremolitic marbles and metasandstanes testify to the presence of a mélange lens within the fault zone A further lens containing peculiar mica- tich schists defines the fault zone separating metasandstones from dolomitic phyllites almost half way between this locality and the South Para River. The microstructural features of the schist blacks within the fault zone can be provisionally correlated with the 8), 5, and S. structures of the area, The meta- morphic wrade of these schists seems (o be that of the upper greenschist or Jower amphi- bolle Caciex, A small stauroliie crystal was found in a specimen of bjotite-rich sehist. Apart from some kinking and bending of mica plates and quartz grains and the introduction of thi stringers of potash felspar, the fault movenjents appear to haye had little effect on the structure of these schists, and the faulting appears to have occurred when the metas- morphic temperatures were too low to permit any significant recrystallisation. The amount of displacement on this fault must be very large judging [rom the meta. morphic diflerences between rocks on either side of the fault surface. Miles (1950) suz- gested a minimum displacement of 5,000 with a probable displacement of ahout 10,000’, Dis- placement of the order of 3 to 5 thousand metres does not seen incongruous, but a better estimate of the amount of displacement must uwail a amore detailed study of the strati- Braphic and metamorphic relationships along mast of its length, burlier workers (Miles 1950; Sprige 1945) have considered the possibility of Tertiary to Recent movements on this fault, the evidence for this being based on the marked fault scarp expression and the occurrence of erosional surfaves and gravel beds of supposed Tertiary uge west of the fault line near Williamstown. However, hills composed of Adelaidean bed- fack in the south-west of the present area are al the samme height on either side of the fault line, and there is no evidence of recéni re- juvenation on the fault surface. The fault acirp i$ believed to be due to the erosive power of the Soath Para River and its tibu- tariey removing the more readily disintegrated biotite zane: phyllites and dolomites west of the tault, after crossing the resistant Warren Infier and iis mantle of metasandstones and schists. This erusional scarp was probibly in existence during the formation of the Tertiary KF MINS gravels and lateritic surfaces near Williams- town, with the Warren Inher and its swirround- ing mantles of high-grade rocks protruding above the Tertizry erosion levels, CoONELUSIONS (£1) Basement-Adeluldean relationships Howchin (1906, 1924) clearly recognised the existence of basement rocks in the porge of the South Para River, south of Williams- lown, and claimed that an unconformity separated the basement from the underlying metasandstones of Aldgate Sandstone type, Hossfeld (1935) claimed to have recognised an actual exposure of the unconformity near the Warren Reseryoir weir, but this could not be confirmed in the present study, Luter workers (Campana 1953: Mills 1963) tailed to recognise a basement inlicr. Campana apparently regarded the lowest schists a5 metu- somatic alteration products of the Aldgate Sandstone equivalent and Mills interpreted the schists below the metasandstone as an early Adclaidean pelitic sequence, The present study hus confirmed Howvhin’s claim for the exisfence oF a basement inlier, Marked struc- tural discontinuity across the observed uncon- formity surface discounts the possibility of an early Adelaidean pelitic sequence. The cosrse- grained schists and gneisses above the mceta- sandstone unit Jithologically resemble the basement yneuses, but they contain mesuscupic structures which may be correlated with unu- logous. structures. in the metasandstone unit and not with structures in the basement gneisses. Io the nearby well-established Houghton Inlier, Spry (1951) showed thal schistosities in the basement and in the Adelaidean mantle were generally parallel. ‘The schistosity in the basement was interpreted as a retrograde schistosity which was associated with the Pulteozvic folding of the Adcluidean succes- sion and updoming of the basement, although tere was some evidence (Spry 1951, p. 120) for shearing of the basement prior to Ade« dsidean sedimentation, Campana (1955) sug- gested that movements in ihe basement of the Adelaide region were responsible for the folding of the Adelawewn sedimentary mantle. the lower beds of which were consequently adjusted into tight folls characterised by sharply overturned anticlines, with attenuated limbs grading into overthrusis and broad ¢ortugated synclings, Talbot (1962) curried out an extensive study of the southern part of SIRUCTURAL CEOLOGY OF WARREN NATIONAL PARK 49 Fig, ¥, Hee alts fa a if shee) Block diagram constricted to scale in orthographic projection on a line of sight plunging 35° towards 253° showing the forms of the principal stractural surfaces in the vicinity of the Warren Reservoir, The structural surfaces shown are the thrusts and faults (cross-hatched), unconformity -etween the basement rocks of the Warren Inlier and the Adelaidean sequence and the lop of the Aldgare Sandstone equivalent (stippled). The surface of the block corresponds to the high water level in the Watren Reservoir but detailed adjustment to the map pattern to allow For topographic variitions have not been made, The F, synform outlined by the unconformity in the centre of the diagram is overprinied by macroscopic be folds, and other Fu folds are seen near the Warren Reservyir, The structural surfaces are folded by larze Fs folds in the southern part of the diagram «nd lesser Fz folds are interpreted to deform the Murray Vale Throst: lo the north of the reservoir. the Houghton Inlier and its Adelaidean mantle abd considered that the chlorite grade base- ment “acted a5 a simple core structure and adjusted to the folding of the overlying Torrens Group" by passive movement along foliation planes produced in a pre-Adclaidean Tetrogressive phase. The present study has established that the lower portion of the Adelaidean succession is welded onta the basement rocks of the Warten Iplier ond that the basement rocks were rejuvenated during the deformation events and the extensive metamorphic recrys- failisation which affected the overlying Ade- laidean sediments during the lower Palacovoic Delaincrian ofogeny. The surface of uncon- formily has been infolded into the basement encisses and there is little evidence of any differential mayement at the boundary between the basement rocks and the overlying sedi- mentury mantle. The basement rocks of the Warren Inlier have undergone 4 partial tee- tonic reconstitution ji which the lower Palaeozoic folds wens imposed on the older pre-Adelaidean structures. (2) Folding of the Adelaidean succession Regional studies in the Mt. Lofty-Olary orogenic arc have indicated that the upper Proterozoic (Adeluidean) and lower Palaeozoic successions were affected by only a lew gentle epeirogenic episodes (Sturtian tectonisin, Dut- tonian folding, Cuassiniaw and Wailpingan movements) prior lo a major orogenic revolu- tion. (the Delamerian Orogeny) in lower Ordo- vician time (Thomson, in Parkin 1969), This ofogenic cycle brought about cxtensive fold deformation, created a helt of low to: inter mediate pressure metamorphism and’ granite intrusion, and brought an end to geosynctinal sedimentation in the Mt. Lofty Range region. The syntectonic Palmer granite, intruded into the core of the metamorphic belt in the eastern Mt. Lofty Ranges, bas been isotopically dated at 490 million years (White, Compston & Kiceman 1967). Detailed structural studies in several key areas in the Mi, Lofty Ranges has established that three important episodes of fold deforma- tion look place at various stages during the ‘ia K. J, MULLS metamorphism, Oller & Fleming (1968) syn- thesized previously published and unpublished work relating to the deformational and meta- rourphic history of the Mf, Lofty Ranges and ussumed that euch of the three folding episodes (F\, Fa and F,) were synchronously developed across the whole deformed belt, but it seems that more key areas will need to be unulysed before this premise can be verified and a satisfactory unravelling of the deforma- tional history is achieved. The present structural study of the upper Prolerozoic rocks around the Warren Inlier has established that three distinct tectonic episodes myolving fold deformation have occurred in succession in relation to meta- morphic recrystallisation, F, deformation Bedding surfaces (Sy) of the Adelaidean succession Were deformed into large regional folds during recrystallisation of the sediments under conditions of rising metamorphic tem- peratures and mica plates and other meta- morphic minefals. grown or deformed syntec- tonicully, developed 9 strong axial surface schistosity fabric (S,) containing an inter- related axis of elongation, 1{S,), which is expressed aS a minecal streaking lineation in some exposures. The commonly observed near parallelism of S, and S, suggests that these early folds possessed an isoclinal style with extensive oear planar limb areas. Mesoscopic F, folds ate apparently rare and difficult to identity, and litthe can be deduced Irom the initial geometry of the F, deformation within the vonfines of the small area studied. Struc- tural analysis of the bedding attitudes in the basul iietasandstone suggested that the hinwe lincs of macroscopic F, folds were gently plunging or subhorizontal and it can be assumed from regional studies elsewhere in the ranwes that the hinge surfaces of the F, folds were dipping stccply cast and striking north- south purullel tu the tread of the orogenic belt (Offler & Fleming 1968), The regional struc- ture which Campana ¢? af. (1955) named The (Lookout Tower overturned anticline can be considered to refer io the demal structure comprising the culmination of the Warren Inlicr, although this culminution is the cam- bined resultant of the Fy, Fy, and F, folding events, ‘Textural-mincralogical evidence sugecsts that metamorphic lemperateres hid reached a peak by the emf of the F, deformation, or during the interkinematic period between Lhe Fy and F, events and the marked metamorphic zona- tion observed in this area Was impressed al this time. In the higher grade schists the mica and quartz grains defining the plane-linear S)-L( $1) labric had developed a coarse praili-size and sillimanite fibres and prisms had grown within the $, surfaces prior to the commencement of the Fo deformation. Despite high-grade mets- morphism sedimentary clasts and textures are slill preserved in must specimens. of the coarser arenites, even in specimens exhibiting @ sirong S,-L(8,) fabric. In those metasediments assumed from their composition to have in- iiated as pelites and semi-peliies recrystallisa- tion and grain growth has obliterated all signs of sedimentary structures in the coarser grained rocks of the sillimanne-muscovile zane, but thin bedding laminations are pre- served in the finer grained schists of she kyanite-andalusite and biotite zones, F, deformation This dclormation episode commenced at or near the peak of metamorphic tenyperature, allowing recryslallisalion and grain growth processex to become dominant over strain preservation in some rocks, and allowing the F, strain effects to outlest grain growth in others. The resus of ihe F; deformation are expressed in two principal forms: (1) The development of intensely appressed folds in the earlier Sy and 5S, surfaces and the imposition of a strong crenulation cleavage- schistosily (Sy) with a north-south strike ane a steep easterly dip, and (2) the development of major late-meta- morphic thrusts which now divide the area up infe several distinct stryotural-metamorphic fumes. The penctrative effects of the F., deforma- lion are most pronounced in the coarse micu- rich schists and gneisses of the sillimanite- muscovite zone where intensely deformed isu- clinal folds in lithological layering have 32 well-developed crenulation cleavage (So} (crenulation of the S, schistosity) grading into a new coarse-grained schistosity as yn axial surface structure. In many exposures the Sy schislosity has become the dominant penetra- tive structure and traces of the former §, schistosity are preserved only in the form of a strong mineral streaking Jineation L(S,-So). The Mount Crawford pranite gneiss formed during the F. deformation and presetves a well-developed S. schistosity and a constantly oriented mineral lineation interpreted as the STRUCTURAL GEOLOGY OF WARREN NATIONAL L(S,-S.) intersection lineation, Basic dykes, intruded helore or during the F, event. re- crystallised to schistose amphibolites preserving a strong amphibole prism lineation, which is interpreted as the result of mimetic growth of hornblende prisms parallel to the .(S,-Sol intersection lineation, The effects of the F. deformation are Jess pronounced in the mutasandsiones. and, although F, crenulations are well developed m the more mica-rich Varieties, intergranular movements were probably daminant, Meso- scopic F, folds in the metasandstones show strong appression und Hattcning of the quariz grains info the S, surface. In some ufcus some of the plastic strain induced im the areniles during the F, deformation outlasted recrys- tallisation and strain relief. leading to the developrnent of well-orientated quartz c-axis fabrics. In the lower grade kyanite-andalusite and biotite zone blocks the FP. deformation is aot 50 apparent and the S». crenulation cleavage is only locally evident, although some local Fy mesoscopic folds are to be found and show a similar tight uppreasion. The Fy, deformation culminated in the ap- pearance of several steep thrusts and mylo- nilic zones iwvolving considerable, but as yet unknown, amounts of displacement, Following the Fy deformation, a sceond static interkinematic period is envisaged in which the strain preservation fromm the Fs deformation became relieved under greenschist fucivs conditions resulting m the exilensrve retrouression of higher grade minerals to quartz, albite, chlorite, sericite and rutile, The sercite has undergone patchy regrowth to larger randomly oriented muscovite crystals, The growth fabrics of these late stage minerals tend to be isotropic except where they were mimetrically controlled. Fy deformtation Most parts of the area covered in the preseril survey were affected hy a rather more brittle deformation late in the metamorphic Nistory resulting in smucrescopic and meso- scopic. folds in earlier structural surfaces. The Fk, deformulion is more pronounced in certain zones. F, folds are rounded te angular and PAKK 311 show varying degrecs of appression. ranging From open warps with eust-west hinge surface trends to tight folds with north-south hinge surface trends and a weakly developed crenus Jation cleavage (S,). Both the hinge surfaces and the hinge lines show considerable varia- tion in attitude, Minerals grown dunng the earlier relrogressive metamorphism became deformed during F, folding and show signs of both plastic and brittle strain. The preserva- tion of such fime F, strain features as quartz deformation lamellae suggests What very little erystal recovery took place after the F, event. The fold deformational history outlined above is in general accord with the conclu- sions of other structural studies carried out in the Mt. Lofty Ranges (Offler & Fleming 1968). At this stage it seems valid to correlate the present results wilh those from the Pewsey Vale area 10 km north-east of the Warren Reservoir where Offler (1966)! found three deformational events in the Adelaidean sue- cession which appear analogous to those described here. In the Pewsey Vale area F, tolds were rare and S, was almost parallel to Sy, some mesoscopic F., folds were deve- loped and open macroscopic Py felds dami- nated the regional structure. Metamorphism had reached its peak late in F; or during F, and was waning during the FP, event, Strong crossed girdle quartz c-axis patterns developed within quartzites after the F, phase but priot to the Fy event. In the adjacent Kanmantoo Group sediments at Pewsey Vale, Offler re- corded two deformational cvents which he interpreted as F, und Fy, with metamorphism oullasting the F, event, In the Cambrai-Spring- ton region Mills (1964)° found that the Kan- mantoo Group metasediments were tightly folded in a dominant early deformational event with focal over'priating by a second fold event with the metamorphic peak being reathed during and folluwing the second event, (3) Faulting Two varieties of faults have been distil guished in the present survey), firstly, faults and mylonile zones considered to be of a high angle thrust type, which developed late in the F, deformational event and wert subsequently folded in the F. event: secondly. a high angle * Offer, R, (1%66)—The stenctuve and metamorphism of (he Pewsey Vale atea, north-east of Williams- _ town, Soulh Ausiralia. Univ. Adelaide, Ph.D. Thesis. : * Mills. K. J. (1964)—The sirucrural petrology of au area east of Springton, Sout Australia, Univ Adelaide. Ph.D. Thesis. 312 reverse fault, the Williamstown-Mcadows fault, which developed after the Fy event and has a tegional significance within the orogenic belt. The late Fy thrusts developed soon alter the pewk metamorphic temperatuses had been treuched and movements continucd during waning Iumperatures. Some strongly schistese retrograde rocks have formed within the thrust zones, including the interesting Williamstown danvourile-kyanite-corundum schists, Dis- Placements on some of these fhiwsts were large, and in the case of the Murray Vale thrust, blocks with considerably different struc- tural and metamorphic character have been brouphe into conjunction. Thrust faults (strike faults, overthrusts) have beeo described from various parts of the Met. Lolty Ranges, but us yet few have been ade- Yitately mapped. Howchin (1906) recognised an vyerthrust helt in the foothills of the Mt. Lofiy Ranges near Adelaide and envisaged an cast lo west movement. Sprigg (1946) desenbed this belt in greater detail and con- cluded that the amount of over-tiding was small. Thrusts und strike faults are also well established on the western side of the Houghton Inlicc (Benson 1909, p. 105; Spry (951; Campana ef a/, 1955). Freytag ( 1957)" recoynised and mapped several strike faults north of Williamstown and his Enterprise Fault may eventually prove to be a continuar ton ef the Murray Vale Thrust of the present survey, A portion al the Wilhamstown-Meudows Fault has been closely mapped in the present survey. I'he outcrop trace o/ the fault surface provides evidence of a stcep easterly dip and the fault may be classed as a steep reverse type (see also Thomson, jn Parkin 1969. p. 108), The actual displacement directions and the amounts of displacement are unknown, but a dip-slip component of 3+5,000 metres dues nop seem incongruous with the observed metamorphic grade differences across. this por- tion of the fault surface. Recrystallisation of dolomitic marbles in the lower grade block aujacenr to the Cuult surface suggests heat derived from fault movement or from a still warm uplifted higher grade eastern block, Erratic schistose blocks carried within the fault zone carry a metamorphic mineral assem- blagé suggestive of lower amphibolite facies K. J. MILLS conditions. It is sugested that movement! on this fault occurred during waning metamor- phism in lower Palaeozoic time, There is no evidence of any more recent rejuvenation of movement on this fault and the present fault scarp is 4 geomorphological erosional feature, Further investigation will be necessary to establish whether the economically important Ukaparinga Fault is a branch of the Williams- town-Meadows Fault or & steep thrust of the post-F. type, (4) Willianistown Window A great deal of confusion seems to have arisen in the previous literature regarding the interpretation and significance of the coarse grained schists ond gneisses in the Williains- town-Warren Reservoir region. These rocks were initially regarded us basement rocks by Howchin (1906, 1926), bur Later workers (e.g. Alderman 1942, Campana 1953, Campana ev al, 1955) considered them to be of meta- somatic origin. Campana (1953) mapped them as the “Aluminous metasomati¢ zone of South Warren Reservoir’ on the Gawler 1-mile Geological Sheet. The present study has establixhed that these Bieisses are in part basement gneisses of the Warren Inlier and in patt metamorphic equivalents of the ower portion of the Ade- laidcan succession. The present author inclines to the view that the schists ancé gneisses may be the result of an isochemical reconstitution of initially alminous pelites of mot unusual composition under high grade metamorphic conditions within the — sillimanite-muscovile zone of the amphibolite facies. Vheir striking texture pnd coarse grain-size is a result of syntectonic crystallisation mear the peak tem- perature of metamorphism within a zone of lacally intense [5 deformation. Adjacent meta- sandstones, although showing remarkably well- preserved cross-bedding, and cyen some clastic grain textures, huve, in fact. been subjected tes similar metamorphic conditions. Later Fs up- thrusting of the Warren Inlier und ifs sur- rounding mantle of high grade Adclaidean metasediments, principally on the Murray Vale Thrust, and later updoming in the Fj phase and subsequent erosion has exposed a unique kind of tectonic windew within which we can examine the metamorphic and structural re- constitution of the pre-Adelaidean hasement " Freytag, FB ('947)—The Vietoria Creek Marble, with observations of the geology of an area north- east Of Williamstown, South Australia, Unt. Adelaide. Honours B.Sc, 'T hesis. STRUCTURAL GEOLOGY OF WARREN NATIONAL PARK and the lower levels of the Adelaidean suc- cession in the core of the orogenic belt, fe is proposed to call this structure the Williamstown Window. Rock units within the window comprise the basement of the Warren Inlier, the basal metasandstones in the Wil- liamstown region, and the overlying coarse- grained Adefaidean schists and onersses belonging to Campana’s "Aluminous meta- samatic zene of South Warren Reservoir”, (5) Economie Considerations li seems apposite to present here a few comments on the structural conirul of same af the economic mineral concentrations within the area surveyed. The Ukaparinga (Unapannga) Copper Mine, Jocated in the north-west corner of the mapped area, was worked in 1350 as the Wheal Fricndship Mine (Brown 1908, p, 137: Cornelius 1940) although apparently littl ore was won. Thete hus been some renewed in- terest in this deposit as 4 low-grade copper prospect in recent years (Blissett 1965). This deposi is located within the Ukaparingu Faull zone which has been traced south of the mime property, From Blissett’s description of the mineralized zone within the mine the fault zone would appear to be dipping 65-70° east, and this fault is a steep reverse type with a very large component of displacenvent, A point uf some interest is that the thick tremo- litic marble bed mapped in the South Para yorge, suuth of the mine, can be predicted to occur within the footwall block bencath the mine, and this might portend a more richly mineralized zone at depth. Tt is not yet knowa whether the Ukaparinga Fault is a branch of the Williamstown-Meadows Fault or is a late F.. thrust fault. Several other copper prospects are located within sinnlar fault zones north of Williamstown. The short-lived Gumeracha and Muunt Crawford Goldfields, located uround Watts Gully in the Mount Crawlord State Forest, were discovered in 1884 and developed as an alluvial field. Numerous shafts were sunk in an attempt to locate the source of the gold, hut the gold was apparently confined ta quartz leaders of small size which proved utpayable (Brown & Woodward 1886), The known gold distribution in this field is confined to the hinge region of a large F, antiform, the Gumeracha Goldficlds Antiform, and it scems likely that the auriferous quarts leaders were loculised wilting (ractires associaled with this brittle Jute metamorphic fold structure. This struc- J|3 tural control may prove to be of some interest in the interpretation ol the distribiillon of other goldfields im the Mt, Lo'ty Ranges, The Williamstown clay deposits have been worked in the vicinity of the Warren Reservoir since early this century, Several older disused mines are located south of the reservoir within the mapped area, especially within north-south zones of highly altered rocks running immedi- alely east of the Wirrianda homestead and east of the road immediately south of the old road bridge, buf the main quarry currently operated is that in section 950, Hundred of Barossa, just outside the north-cast edge of the mapped area. Many reports have been wrillen On these deposits but hitherto no important structural control has been recognised. Jack (L926) sug- gested that the kasolinisation and hydromica development was preater than would be expected by weathering alone and suggested some Form of introduction. Cornelius (1932) indicated that the deposit in section 950 dipped steeply east and had a southerly pitch. Alderman (1942, 1950) concluded that the cluy deposits had largely originated through the hydration of an original body of massive decussately textured sillimamite rock and erected an elaborate metasomatic scheme to explain the various phases present and the sudden changes from low grade to high grade rocks. Alderman (1942, p. 8) states that “there dovs not scum to be any major structural feature separating the aluminous rocks Irom the low grade rocks”, Later workers (Gaskin & Sampson 1951, p. 60; Betheras 1953; Cochrane 1954, p. 54: Cochrane 1955, ». $5) generally accepted Alderman’s views, and although there are references fo various damourite shears and small faults, these are cunsidered to be of minor importance. and perhaps cue to volume changes during metu- somatism, The clay deposits appear to be irregular in distribution and this was related fo the fortuitousness of metasomatism. The clay deposits north of the reservoir were not studicd by the author, but pre- liminary observations have tndicaled that the Murray Vale Thrust passes through the centre of the large quarry on section 950 and separates the highly altered sillimanite-kyaqite bearing rocks to the west front the low-grade “clay-states" to the east. It the vicinity of the quarry the Murray Vale Thrust is ap- parently involved in Several tight F, folds, Tn terms of the structural history deter- mined for the schists occurring south of the js K, J. MILLS reservoir, the following series of events is envisaged us controjling (actors in the forma- tion of the clay deposits, The original mussive sillimanite-rutile rocks are thought to have crystallised within the sillimanile-nmiuscovite zone schists and gneisses at the peak of metu- morphism under static conditions during the interkinematic period between the F, and F, deformation events, The origin of the silli- manite remains obscure, but presumably same form of melasomatic transfer was involved. During the Fy, event, whilst the country rocks were being intensely deformed and reconsti- tuted. a number of damourite-kyaniles. corun- dum shear zones developed within the tectonic- ally resistant sillimanite pods and late in the F, event several strong thrust zones appeared, and the subsequent passage of hot aqueous solutions within the thrust zones altered the sillimanite deposits to clay. It is considered that the sillimanite and damonrite-kyanite deposits may be structurally controlled within early incipient zones of [F. Uhrusting, but this will need further investigation. The subsequent development of clay within some of the silli- manite bodies may have required the presence of open channelways along zones of tuter movernent and could be enhanced by the deve- lopment of strong Fy folds in the vicinity of section 950, (6} Sanpnary The following list of events summarises the proposed geological histary for the Warren Reservoir region:— {a) Deposition of pre-Adelaidean sediments of the Warren Inlier. These sediments were largely pelitic and homogeneous with some quartzofelspathic units and minor mars. (b) Deformation of the pre-Adclaidcan sedi- ments of the Warren Unlier. Several phases of folding, as yet unravelled, accompanied this deformation, with metamorphism (o upper greenschist or lower amphibolite facies at most, There gre no intrusive tocks, apart from pegmatices. no volcanics, no rocks of “Houghton diorite” type, and no evidence for a phase of pre-Adelaidean retrogression and phylonitisation, (c) Krosion to 4a peneplain surface, (d) Deposition of the Adelaidean sequence, consisting of a basal cross-beddled felspathic sandstone followed by a pelitic sequence grad- ing upwards into more calcareous or dolo- mitic sequences. (c) Deformation and metamorphism of the Adelaidean succession in the lower Ordovician Delamerian orogeny. Three compressive events accompanied this orageny and metamorphism locally reached the sillimasite-muscovile zone of the amphibolite facies within and adjacent to the Warreb Inlier A locally important phase of thrusting from the east accompanied and followed the second compressive event under conditions of waning metamorphic tem- peratures. The third compressive event, ol more brittle character, occurred during low metamorphic lemperutures and played an im- portant role in the development of various mineral deposits, (1) Formation of the Wilhamstown- Meadows Fault as a major plane of discon- linuily extending along most of the length of the central Mount Lofty Ranges. ‘This fault ts responsible for bringing the higher grade meta- morphic zones of the eastern Mount Lolly Ranges into conjunction with the lower grade zones of the western Muunt Lofty Ranges. Displacement on this fault occurred in the early Palacozoic and there is no evidence of subsequent rejuvenation of movements. (zg) Extensive denudation and peneplanation and development of a marked fault scarp ero- sional feature along the Williamstown. Meadows Fault in the Williamstown region through the differential erosion of (he lower grade phyllites by the South Para River. Acknowledgements The author is grateful for the co-aperation of the various public autboritics and private individuals who have permitied access to pro- perty fo make this study possible, The project Was completed in the Department of Geology and Geophysics, University of Sydney. Mr. R- Sealy kindly axsisled with photographic work associated with the construction of the figures. Mrs. J, Neilsen as especially thanked for her patient redrafting of figure t. Mr, Glenn Kulson yssistel with the lettering on figure 2 and the map legends, Mrs. R. McKenzic typed the final manuscript. The venerous sup- port of the University of Sydney in enabling the completion of this work is gratefully acknowledged. References ALDERMAN, A. R. (1942).—Sillimanite, kyanite and clay deposits near Williamstown, South Australia. Trans. R. Soc. 8S. Aust. 66, 3-14. ALDERMAN, A. R. (1950).—Clay derived from sil- limanite by hydrothermal alteration. Minera- log. Mag. 29, 271-279. BENSON, W. N. (1909).—Petrographical notes on certain pre-Cambrian rocks of the Mount Lofty Ranges, with special reference to the geology of the Houghton District. Trans. R. Soc. S. Aust. 33, 101-140, BETHERAS, F. N. (1953) —Clay deposit—Williams- town. Min. Rev., Adelaide, 95, 108-113. Burssett, A. H. (1965),—The Ukaparinga (or Unaparinga) copper —_mine—Williamstown. Min. Rev., Adelaide, 122, 47-57. Brown, H. Y. L. (1908).—‘Record of the Mines of South Australia”. (Government Printer: Adelaide. ) Brown, H. Y. L. & Woopwarp, H. P. (1886).— Notes on geological map of Gumeracha and Mount Crawford Goldfields. Parliamentary Papers of S. Aust. Paper 179. CAMPANA, B. (1953).—Gawler map sheet, Geo- logical Atlas of South Ausiralia, 1:63,360 series. (Geol. Surv. S. Aust.: Adelaide.) Campana, B. (1955).—The structure of the eastern South Australian ranges: The Mount Lofty- Olary Arc. J. geol. Soc, Aust. 2, 47-62. CAMPANA, B., GLAESSNER, M. F., & WHITTLE, A.W. G. (1955).—The geology of the Gawler Military Sheet. Rep. Invest. Dep. Mines S. Aust. 4. CocuraNne, G. W. (1954).—Warren refractory shale. Min. Rev., Adelaide, 96, 51-55. CocHraNe, G. W. (1955).—Williamstown mineral deposits. Min. Rev., Adelaide, 98, 77-111. Cooper, J. A. & Compston, W. (1971).—Rb-Sr dating within the Houghton Inlier, South Australia. J. geol. Soc. Aust. 17, 213-220. CorneLius, H. 8S. (1932).—Fireclay deposit near Williamstown. Min. Rev., Adelaide, 56, 79-80. GASKIN, A. J., & SAmpson, H. R. (1951). —Cera- mic and refractory clays of South Australia. Bull. geol. Surv. S. Aust. 28, 59-64. Hosps, B. E. (1971).—The analysis of strain in folded layers. Tectonophysics 11, 329-375. Hossre.p, P. S. (1935)—The geology of part of the northern Mount Lofty Ranges. Trans. R. Soc. S. Aust. 59, 16-67. Howcuin, W. (1906).—The geology of the Mount Lofty Ranges. Part (ii). Trans. R. Soc. 8. Aust. 30, 227-262. Howcuin, W. (1926).—The geology of the Bar- ossa Ranges and neighbourhood in relation to the geological axis of the country. Trans. R. Soc. S. Aust. 50, 1-16. Jack, R. L. (1926).—Clay and cement in South Australia. Bull. geol. Surv. S. Aust. 12, 56-57. MILEs, K. R. (1950).—The geology of the South Para Dam project. Bull. geol. Surv. S, Aust. 24. Mitts, K. J. (1963).—The geology of the Mt. Crawford granite gneiss and adjacent meta- sediments. Trans. R. Soc. S. Aust. 87, 167-183. OFFLER, R., & FLEMMING, P. D. (1968).—A syn- thesis of folding and metamorphism in the Mt. Lofty Ranges, South Australia. J. geol. Soc. Aust. 15, 245-266. Ramsay, J. G. (1962).—The geometry and mech- anics of formation of “similar” type folds. J. geol. 70, 309-327. Ramsay, J. G. (1967).—"“Folding and Fracturing of Rocks”. (McGraw-Hill. ) Spricc, R. C. (1945) —Some aspects of the geo- morphology of portion of the Mt. Lofty Ranges. Trans. R. Soc. S. Aust. 69, 277-303. Spricc, R. C. (1946).—Reconnaissance geological survey of portion of the western escarpment of the Mt. Lofty Ranges. Trans. R. Soc. S. Aust. 70, 313-347. Spricc, R. C., WHITTLE, A. W. G., & CAMPANA, B. (1951).—Adelaide map sheet, Geological Atlas of South Australia, 1:63,360 series. (Geol. Surv. S. Aust.: Adelaide.) Spry, A. H. (1951)—The Archaean complex at Houghton, South Australia. Trans. R. Soc. 8. Aust. 74, 115-134. Tacsot, J. L. (1963).—Retrograde metamorphism of the Houghton Complex, South Australia. Trans. R. Soc. S§. Aust, 87, 185-196. TaLeorT, J. L. (1964).—The structural geometry of rocks of the Torrens Group near Adelaide, South Australia. J. geol. Soc. Aust. 11, 33-48. Tuomson, B. P. (1969).—The Kanmantoo Group and early Palaeozoic tectonics. Jn L. W. Parkin (Ed.), “Handbook of South Australian geology”, pp. 97-108. (Geol. Surv. S. Aust.: Adelaide. ) Wuite, A. J. R., CompstTon, W., & KLEEMAN, A. W. (1967) .—The Palmer Granite—A study of a granite within a regional metamorphic environment. J. Petrology 8, 29-50. WooLNouGu, W. G. (1908).—Notes on the geology of the Mount Lofty Ranges, chiefly the portion east of the Onkaparinga River. Trans. R. Soc. S. Aust. 32, 121-137. OBITUARY: THEODORE GEORGE BENTLEY OSBORN, D.SC., M.A., F.L.S. Summary THEODORE GEORGE BENTLEY OSBORN D.SC., M.A., F.L.S, OBITUARY THEODORE GEORGE BENTLEY OSBORN, D.Sc., M.A,, F.L.S. 2.x.1887 -3.vi.1973 Theodore George Bentley Osborn was born in England and educated at Burnley Grammar School and the University of Manchester. He spent just over half of a long and energetic life in Avstralia, occupying Chairs of Botany at Adelaide and Sydney Universities and later the Sherardian Chair at Oxford University, On retirement he chose to return to Adelaide. Osborn's research during the period 190#- 1912 was on the fungi, when he was u lecturer in Economic Botany in the University of Man- chester, In 1911 he was awarded the M.Se. degree, and in 1920 the D.Sc. degree, from the same University. In 1912, Oshoen was invited to become Pro- fessor of Botany, Vegetable Pathology and Parasitology in the University of Adelaide, eombined with the office of Consulting Botanist to the Government of South Australia, and his publications over the next nine years strongly reflect the nature of this appointment, Shortly before coming tu Australia, he mar- ned Edith Muy Kershaw, M,Sc-., Assistant Lec- turer in Botany in the University of Manches- ter. They had three sons, Peter, Andrew, and Richard, all of whom served in World War IT; Andrew, an R.A.F, pilot, was killed in action in 1942, When he established the Department of Botany in Adelaide in 1912, Osborn was only 25 years old and youthful in appearance, He was fond of the story of how he went into the examination hall, which was being supervised by a middle-aged woman who had not met him, and asked for the Botany I paper. She brought him the paper and when he said “and while 'm here [It have a look at the Agricultural Botany paper too" she replied, “You'll do nothing of the sort, young man, you'll just sit down there and get on with your Botany I.” Osborn developed the first degree courses in Botany at Adelaide University, though Botany courses had been given earlier under Professor Ralph Tate. He took most of the teaching until 1916 when a demonstrator was appointed, fol- lowed in 1922 by a lecturer in Plant Pathology. The latter appointment, and the establishment of the Waite Agricultural Research Institute in 1925, relieved Oshorn from much of his time- consuming advisory work. However, in 1926 he was asked by the executive of the recently formed Commonwealth Council for Scientific and Industrial Research to review botanical work in progress in Ausiralia, and further to report on plant problems in Australia. In. 1927 he was appointed adviser to the Council and was offered the dircctorship of their Division of Plant Industry. However, at about this time he applicd for the Chair of Botany at the Uni- versity of Sydney, lo which he was appointed in 1928. During the early years of his residence in Adelaide, Osborn deVeloped interests in plant ecology, studying areas near Adelaide as well as distant ones, stich as Franklin Island and the Pearson Islands, off the west coast of Eyre Peninsula. During a visit by Professor R. S. Adamson (University of Cape Town), joint studies were made of the ecalogy of the Ooldea district and of Eucalypries Forests of the Mount Lofty Ranges. ‘These. studies: were published in the Transactions of the Royal Society of South Australia. Osborn also published on two primi- tive lycopods, (Isoetes and Phylloglosswn), found for the first time in South Australia. These ecological studies led to Osborn's great interest in the vast arid region of South Aus- tralia. He made numerous visits to the saltbush areas and developed cordial relationships with pastoralists. This culminated in the generous gift of Messrs. Hamilton, Wilcox Ltd., in 1925, of the Koonamore Vegetation Reserve, which is now the oldest biological station, with con- tinuous records, in Austrolia, The reset've, ‘Trans, HM, Soc. S. Aust, Vol 97, Part 4, 30 November, 1973 318 located 385 km NNE of Adelaide, was re- named the “T, G, B. Osborn Vegetation Reserve at Koonamare” i) |972. The first important work on grazing and regeneration of natural Vegetation its chese arid regians resulted from the collaborative work of Osborn and his two colleagues. J. G. Wood and T. B- Paltridge. The reserve and nearby areas are still used extensively by stall and students of the Ade- laide Botany Department. in 1928 Osborn became Professor of Botany at the University of Sydney and he set about rvorganising the undergraduate courses there. He took the first year lectures and those in plant physiology, as well as in ecology. At first he continued to clear wp his ared zone research, relaining direction of the Koonamure work uotil 193), but increasingly he became in- terested in the vegetation of coastal New South Wales, In [930 he gave the Livingstone Lee- Iures enuiled “Plaot Life in the Sydney Dis- trict", with an ecological upproach. He was interested in the xerophytic propertics of the plants characteristic of this relatively high Tain- fall area. In 1932, his Presidential Address to the Linnean Socicty of New South Wales. was on “The Plant i Relation to Water’, with spe- cial reference to the properties of xerophytes in being able to withsiand drought. Later, O3- horns work itt ecology stimulated the interest of his students in descriptive ecological accounts of other parts of New South Wales, including one on the ecology of the Myall Lakes vegetation, jointly with R. N, Roherlson. During his time in Australia, Osborn was an aclive member of 4cientific societies. He was 4 stroug supporter of the Royal Society of South Australia, contrihuting several papers uml berng a Fellow since 1913 and Honorary Fellow since 1955. He was a Council Member 1915-20, 1922-24, Vice-President 1924-25, 1926-27, anu President 1925-26. He played an active part in the establishment of Flinders Chase on Kungaroo Island, being a member of the board from 1919 to 1927, and Honorury Secretary and Treasurer 1921-25. Oshom was alsa a member of the Linnean Society of New South Wales from 1928 and President in 1932, and President of Section M (Botany) of A.N.Z.A.AS. in 1928, and a Vice-President from 1924-25, The Royal Society of New South Wales awarded him the Clarke Medal in 1958. Osborn became Sherardian Professor of Holany aid a Fellow of Magdalen College, Ox- ford, in 1937, The Oxford Department was very poorly housed in cramped surroundings in an antiquated building in the Oxford Botanic Giarden. This Bolanic Garden, founded in 1621, had been somewhat neglected. but Os- born stinvulated collaborative work with the Garden, which continued strongly after the Department moved into the new laboratories planned by him and consteucted shortly before his retirement in 1953. Oshorn's achievements ut Oxford have been summarised in his obituary in TRe Tintes for 6 June 1973~—-There can be nu doubt that under him the study of botany m Oxford achieved an eminence which it had not before reached even under more famous Sherarlian Professors. Not only was the production of original work in botany greater in quantily and quality than ever before but of the undergra- duates, demonstrators and research men pre- sent in Oxford during his tenure of the chair, eleven of more are or have been Professors and heads of departments, and several mure Readers in biological departments of Univer- sitics in Britain and clsew here.” In 1953, Osborn retired from the Chair at Oxford sad returned to Australia, After a period of residence in Adelaide, in 1957 the Osborns moved to Melbourne where Mrs. Os- born dicd a year later. Following this, Osbora returned to Adelaide to live. During 1959 he was Acting Master of St, Mark's College, of which he had been one of the founders in the carly 1920's, In 1962, when the Botany Depart- ment celebrated its 50th anniversary, he was appointed Professor Emeritus of the University of Adelaide, having been given a similar title at Oxford University on his retirement in 1953, Osborn left Oxford well known, among other things, for his course on Gyminosperms, ane in Adelaide he was invited by Penfessor J. G. Wood to give 4 course oo this group of plants to third year students. This he contrnusd to do for five or six years, and in 1960 published his last paper, on the embryology and life history of Podevarpus faleatus. Osborn had long in- tended writing a book on the Gymnosperms, but unfortunately this never came to fruition Osborn made his home at St. Mark's College during 1959, where he was associated with the very capable seerctary Marjoric Sabine, whom he married in England in 1960. Both Professor and Mrs, Osborn took an active part in the life of the Botany Department from then on, and Osborn attended the weckly seminars until shortly before his death, Oshorn was a good lecturer and teacher who attyacted students of quality, His influence was passed on toa several of the present leaders in Australian plant ecology, and among his many Australian students were: J. G, Wood (for- merly Professor of Botany, Usmversity of Ade lade}, Ci. Samuel (formerly Deputy Chiel Szientific Officer of the Agricultural Research Council, WK), G. J. Rodger (formerly Direztor-General of Forestry, Canberra), B, H. Bednall (formerly Conservator of Forests, South Australia), T. B. Paltridge (formerly Chief Scientific Liaison Officer, C.S.1.R,0,), N. A. Burges (formerly Professor of Botany, University of Sydney, and Vice-Chancellor, University of Northern Irclandi, M.R. Jacobs (formerly Director-General of Forestry, Can- berra). D. Martin (Officer-in-Charge, Tis- mangn Regional Laboratory, C.S.1R.O.), H. K. C. Mair (formerly Director and Chief Botanist, National Herbarium, New South Wales), BR. N. Robertson (Director, Research School of Biotogical Sciences, Australian Na- 31y tional University), Lilian Fraser (formerly: Chicf Biologist, Division of Science Services, N.S.W, Department of Agriculture), Joyee Vickery (formerly Scoior Botantsi, N.SW, Department of Agriculture), N.C. W. Beadle (formerly Professor of Botany, University of New England), Gwenda Davis (formerly Asso- claie Professor uf Botany, University of New England), N, H. White (formerly Professor of Plant Pathology, University of Sydney), and Ilnva Brewer (née Pidgeon, School of Bio- logical Scienzes, University of Sydney). Osborn died after a short illness on 3 June 1973. He will be long remembered in Australia Yor the mfluence he had on Botany im Adelaide and Sydney, and particularly for his qualities of leadership and inspiration of younger people, He always had the huppy knack, even m his later years, of being able to talk with Students, lo be interested in what they were doing, und to cutch their interest in his ex- periences. —R. N. Robertson and C. M- Eardley. Bibliography 1909 The Dowels of some Egyptian coffins of the X1ith Dynasty. Mem. Proc. Manche lit, phil. Soe. 53 (9), 1-5, T4Q9 The seab diseases of potatoes, Aun, Rep. Trans. Marchr mricras, Soe, 909, 61-69. 1909 The fateral roots of Amvelon radicans and their mytorhiza. dun, Bot, 23, 603-611, 1909 A note on the staminal mechamsm of Passi flora caerulea. Mem, Proe, Manehr lit, phil. Sac. 54 (3), 1-7. A preliminary noie on the life history and cylology of Spangaxpora subterranca. Ann. Bor, 25, 271. Spongospora subterranean (Wallroth) Iobn- son. Ana. Bot, 25, 327-341. The life cycle sad affinities of the Masmo- diophoraceac, Brit. Assoc, Report. Ports- mouth, p. 572. 19/2 Moulds and mildews: their relation to the dumuging of grey cloth and prints, f. Soe, Dyers Colane, 28 (6), 1-14. 1912 Preliminary observations on the mildew of grey cloth. Journ, econ, Biol 7, 58-63, 1912 A note on the submerged Corest at Tlanaber, Barmouth, Mem, Proe, Manchr lit, phil. Soe. S$ (16), 1-10. 1912 The leaf-scorch disease of celery. J. Dep, Agric. &. Ans. 16, 402-405, 1913 A bacterial disease in potatoes. J. Dep: Arric. §. Aust. U7, 19-21. 1915 The Jeaf-spot disease of lucerne. J. Dep. Agric. §. Awst, U7, 294-296, 1914 “Botany.” Editor and part author of article in “Handbook of South Australia”, pp, 251- 273, BA,A.S, (Goyt. Printer: Adelaide.) 1911 WLI 19) 1914 Plant Pathology, Je “Handbook af South Australia”, PP. 186-189. BAAS. (Govt, Printer: Adelgide,) 1914 Notes on the fora around Adelside, South Australia, New Payni. 13, 190-221. 1914 Types of vegetalidn on the coast in the neighbourhood of Adelaide, South Australia. Brit. Assoc, Report, Aust., 584-586. 1915 Same new records of fungi for South Aus- tralia. Yrans. R. Soc. S. Aust. 39, 382-356. 1915 Observations on the morphology af Sela: ginella uliginaxe, Spring. Brit. Assoc, Report, Manchester, p, 727. 1915 Some observations ou potata scab in South Australia. J. Dep, Agric. ¥. Aust. 18, 497- 503. Rust of wheat, #, Dep. Agric. §, Att. 20, 9-28. 1916 Health and disease in plants, J, Dep. Agric. S. Aust. 20, 89-101. 1916 A nole on the oeeurrence and method of formation of the resin (Yacca Gum) in Kantherrhoed quadrangulata. Tras, R, Sec, S. Aust, 40, 1-8. 1917 Solanvm vasrratum—a new weed plant. J, Dep. Agric, S. Anst, 20, 783-734. L917 Flea Secd—-a new weed plant. J. Dep. Agri. S, Anat, 2, 360-362, (917 Polato Wilt. J, Dep, Agric, S. Awst, 20, 864- B65. (917 Offieinul plants. J. Dep. Agric. S. Anse. W, ORO-98 1, 1918 fsolama petree—a suspected poison plant. J, Dep, Agric, 8, Aust. 22, 50-32. ; 1918 Report of the Consulting Boltanist and Vege- table Pathologist, Rep, Min, Agric. S, Aust, year ended June, 1918, pp. 30-32.. [S16 [923 1924 On the habitat and the method of occurence in South Australia of two genera of lyco- pods hitherly unrevorded for whe State, Trans, Ry Soc, &, Awsi. 42, 1-12, Some. observations on the tuber of Phylle glostnm. Ann. Rat. 33, 485-516. | Black-ley disease of ¢abhages, J) Dep. Ageic S, Aust 23, (07-F10. Two serious new wilt diseases f, Dep, Agric, S. Ast, 23, 437. Report of the Consulting Botanist and Veac- table Pathologist, Rep. Min. Agric. 3. Aun. year ended 30rh June, 1919, pp, 29-32, Downy mildew in South Australia, #2 Dep. Agric, &. Aust. 24, 100 Black spot of the vine, J. Mer. Agric. ¥. Avs, 25, 29-30), Downy mildew. J. Dep. Agric. S. Aust. 25, 120-125, Report of the Consulting Butanist and Vege- table Pathologist, Rep, Mia, Agric. S. Aust, lor year ended 30th June, 1920, pp. 64-66. Notes on two vine diseases which occurred on the River Murray in October, 1921. J. Dep. Aerle, 8, Aust, 26, 225-230. (With G. Samuel.) Report of the consulting botanist and vege- table pathologist. Rep, Min. Agric. §.. Atese. for year ended 30th June, 1921, Some observations on /sovles drumtruneli¢ A.Br. Anatamy, din. Bor. 36, 41-54, Nole on the pathological morpholowy of Cintructia yplnificis (Ludw.) McAtp, Trans, R. See. S$. Aust. a6, 1-5. Flora and Fauna of Nuyt's Archipelago, No 3. Sketch of the ecology of Franklin tslumds- Tran. R. Sec, 8, Anst, 46, 194-206, On the ecology of the Ooldea district, Trans. R. Sve, S. Aust, 96, 339-564, (With RS, Adamson. } Some new records of fungi for South Ans- tralia, Pr. 2. Together with a description of 4 pew species of Pieeemlu, Trans. R, Sec. N, Aust, 46. 166-80. (With G, Samuel.) Flora and Fauna of Nuyt's Acchipclago sod the Investigator Group, No. &: Ecology of Pearson Island with an app. on the soils by J, G. Wood. Trans. R. Sac, S. Aust. AT, 97-118. On the zonation of the vegelation in the Port Wakelield district. Crans. Ro Sec. 8. lust, 47, 244-254, (With J. G. Wood.) On some halophytic and non-halophytic plant communities in arid South Australia. Traay R, Soc. 8, Aust, 47, 388-399, (With J. G. Wows.) The ecology of the Eucalyptus Forests of the Mount Lofty Runges (Adelaide District). South Australia Trans, R. Soe. S, Arist. 48, 87-144. (With R. S. Adamson.) Annual Report of the Consulting Botanist and Vegelable Pathologist. S. Anst. Dep. Apne. Report of the Min. for year ended apth June, 1923, 66-68. The fiora and fauna af Nuyt’s Archipelago und the Investigator Group, No. 18: Notes on the vegetation of Flinders Island. Travey. R. Sve, S. Ans, 49, 276-287, 1925 1926 1926 1926 1926 1927 1928 1928 Izy 1930 1931 1932 1932 1932 1935 1937 1939 1939 (947 195] 1960 On the ecology of the Vexetalion of arid Australia, No. 1. Introduction and general description of the Koonamore Reserve tor the study of the saltbush flora, Treas. R. Soe, Sy Aust, 49, 290-297_ pl, 24. The fodder plants of arid Australia. Pastoral Rev. Nov, 16, 1925 Annual Report of the Consulting Botanist and Vegetable Pathologist. §. 4s Dep, Apri Report Min. fur year ended 3th June, 1925, Annual Report of the Consulting Botanist and Vegetable Pathologist, S. dan Dep Agric. Report Min. Tor year ended th Tune, 1926. Methods af Work in arid and semi-arid Aus- tralia, de A. G, Tansley & T. F, Chipp. “Aims and methods in the study of vevela- ion”, pp. 269-273. Veectation in arid parts of Australla, Ausf. aan Ady. Sci. {Perth Meeting) 18, 823- 24. Regeneration problems in arid Awstralia. 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