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The paper discusses the botanical perspective of the Quaternary research in the light of phenomenal and revolutionary progress ushered in by the oceanic research of deep sea cores and long uninterrupted terrestrial sequences. It is suggested that the botanical parameter should be equipped sufficiently and the dynamic nature of climatic requirements of plant species must be taken into consideration for past inference of environmental syndromes and for its overall applicability so that the consumer disciplines are not misled.

The paper reports for the first time from India the discovery of spikelets of Setaria spp. It appears that the carbonized grains are represented by Setaria italica, S. viridis and S. verticillata or by unknown species. The material comes from the Harappan site, Surkotada in district Kutch, Gujarat and is radiocarbon dated to 1600 B.C. The identification of these carbonized spikelets is based upon comparative morphological study of ten extant species of Setaria.

In the light of fresh and exhaustive information now available on the ecology of vegetation of the Rajasthan desert, the reinterpretation of the published pollen diagrams reveals that there was increasing trend towards dryness until 5,000 years ago and thereafter between 5,000-3,000 years ago the environment was characterized by maximum warmth and dryness and by high velocity winds and dust storms. The precipitation which was within the range of 150-400 mm showed a gradient from the extreme west of the desert to its east. The renewed sand dune activity during the hypsithermal period had encroached upon the eastern tracts of the desert. The salt lakes which had originated about 10,000 years ago had already high salt content in their waters and during a continuous phase of recession in the entire Holocene rose once between 6,000-5,000 years B.P. The vegetation had comprised of Calligonum series and Prosopis-Capparis-Ziziphus series in the vicinities of Lunkaransar, Didwana and Sambhar and of Anogeissus-Acacia series in the vicinity of Pushkar lake. The earliest farming episode did not precede 5,000 years B.P. though inexplicable evidence of burning and disturbance of vegetation preceded it perhaps caused by natural means and grazing of animals. The subsequent desertification was caused by combined effect of climatic and biotic factors.

The overview appraises critically the work on Quaternary palaeobotany/palynology carried out in the Himalayas during the last hundred years. The fluctuations in cool and temperate vegetation and climate during the early Quaternary (Lower Karewas), aspects of vegetational development during the last glacial and during the present inter-glacial period impart a glimpse of the changing patterns of vegetation through the Quaternary period. Further, it urges the construction of more pollen diagrams, intensification of research on the comparative database together with increased indigenous ecological insight and the sophistication in methodology to bring out invaluable information of biogeographical, geological and archaeological interests. The history of lake basins and fluctuations in hydrochemistry should be built up through the studies of diatoms in conjunction with pollen and spores. The studies of the evolution of Quaternary floristics should not overlook the historical perspective, i.e, its evolution from the Miocene/Pliocene flora. The recognition of the transitional stage in the evolution of flora is highly imperative to demarcate the Neogene/Quaternary boundary on botanical grounds. A few names for various stages (vegetational/climatic phases) during the Quaternary have been proposed after the type sites in keeping with the Code of Stratigraphical Nomenclature for their use in bio-and chronostratigraphy. Besides, it emphasises the importance of indigenous ecological insight in solving the ecological problems and biogeographical riddles in the diversity of floristics in the Himalayas and determines the rate and extent to which the forests in the Himalayas have been adversely affected by the progressive increase in land use and by the progressive and selective exploitation of the forest constituents.

The pollen analysis of 6 m profile from the brackish water shallow Nal Lake about 60 km south-west of Ahmedabad reveals the Holocene history of the grassland-chenopod savannah in its vicinity. The chenopods show a declining trend from early Holocene to 3,500 years B.P. and Holoptelea integrifolia, a tree member of the riverain dry deciduous forest, shows a rising trend until 4,000 years B.P. Three episodes of estuarine conditions, before 7,000 years B.P., between 3,500-6,000 years B.P. and around 160 years B.P. are recorded. These may be ascribed to the repeated overflowing of the flooded Little Rann caused by marine inundation possibly as a result of the tectonic disturbances. The lake had perhaps originated as a marine inlet.

The Radiocarbon Dating Laboratory of the Institute was established in 1974 primarily to assist in the program of research undertaken by the Institute's Department of Quaternary Palynology (Rajagopalan and Vishnu-Mittre, 1977). The measurements carried out by the Laboratory up to December 1977 are presented in this date list.

The paper discusses the botanical perspective of the Quaternary research in the light of phenomenal and revolutionary progress ushered in by the oceanic research of deep-sea cores and long uninterrupted terrestrial sequences. It is suggested that the botanical parameter should be equipped sufficiently and the dynamic nature of climatic requirements of plant species must be taken into consideration for past inference of environmental syndromes and for its overall applicability so that the consumer disciplines are not misled.

Pollen analysis of fossil soils along the bank of Ghod River, Inamgaon, Maharashtra, suggests the former occurrence of a dry deciduous forest dominated by Holoptelea integrifolia. The annual precipitation then was not higher than now and an environment of unstability of soil concentration along the banks had prevailed. The subfossil soils were formed by ponding of flood waters when the water level in the river had risen much higher than at the present caused probably by tectonic movement in the catchment area. The percentage distribution of pore apertures on subfossil pollen grains of Holoptelea integrifolia has been found to differ considerably from the modern plants of this species suggesting a physiological change in the modern plants.

The mangrove swamps in Bombay and Salsette islands are made up up to 5 m of dark and brown mud filling undulating rocky basins. Pollen analysis has revaled statistical insufficiency of pollen grains, the identification of which permits us to infer broadly an increase of Rhizophorae (Bruguiera and Ceriops) in the top samples; Avicennia was poorly present and there are indications of the presence of the other important mangrove genera among which pollen grains of Sonneratia acida outnumber those of others. The sediments have been found to abound in microplankton and microforms, and the latter have indeed escaped the destructive effects of the acetolysis method. The lack of organic matter and poverty of pollen have not permitted the building up of radiocarbon dated pollen stratigraphy for these mangrove swamps. The possibilities for the prevalence of relatively moister climate in the past have been discussed.

The problem of the delimitation of the boundary in the N.W. India is discussed in the light of the recent developments in the concept of demarcating this critical horizon. The suggested position of this boundary is largely based upon the biological evidence with subsequent climatic indication. The boundary is not found to be synchronous with the glacial epoch, rather it precedes it. The paper suggests the placing of the boundary at the base of the Pinjor stage in the Upper Siwaliks and towards the bottom of stratigraphical zone 1 (after De Terra and Paterson) of the Lower Karewas.

The paper gives an account of a qualitative and quantitative systematic enumeration of fungal spores and other remains from the Flandrian deposits at Holme Fen and Trundle Mere in the Whittlesey Mere region, Hunts., England. An attempt has also been made towards the correlation of populations of fungi with the various peat types, as a result of which it has been established that certain spore types have frequency variations that are correlated closely with the vegetation of given peat layers more particularly with the brush-wood peat, the Cladium sedge peat and the Phragmites peat. It has indeed been found difficult to correlate the various fungal populations with the peat types of the raised bog for lack of knowledge of their hosts in the bog peats. The paper also discusses the prospects for the investigation of sub-fossil fungal spores particularly in regard to the role they play in the formation of peat types, their history and distribution in the various periods of the Quaternary era, and in regard to their ecological considerations.

The paper describes several new anatomical details regarding the vegetative remains of the Pentoxyleae. In the genus Pentoxylon Srivastava stems possessing more (8-9) or less (3-4) than the usual number of the steles are described. Besides the scalariform pitting, bi-and multiseriate medullary rays-characters not known before-are also described. The genus has been diagnosed for the first time. The apical region of a dwarf shoot of Pentoxylon sahnii is described. The genus Nipaniophyllum Sahni is reinvestigated and consequently the diagnosis of both the genus and the species N. raoi Sahni emended. The stomata in the genus are shown to be non-bennettitalean in nature. The stems of Nipanioxylon guptai Sriv. are described. In the light of new information along with the previously known facts it is shown that the Pentoxyleae is not a synthetic group and belongs to the Cycadophyta. It is the most primitive group amongst the cycadophytes and should rank with the Benuettitales and the Cycadales.

The pollen analytical investigations carried out at Sankrail and Jangalpur, Howrah, in the Bengal basin has shown that the fresh water Heritiera forest with a slight brackish water conditions existed during Late Quaternary time and the sites have remained far remote from the Sunderbans as evidenced by the occurrence of Potamogeton. From pollen sequence there is hardly any indication of change in climate from the present during the last 6000 years in the Bengal basin. The profiles from Sankrail have been radiocarbon dated to T.F. 856-5810 ±110 B.P.-top of the bottom clay, T.F. 855-4720 ±135 B.P.-top of the peat layer in Sankrail Pit 2 and the peat layer in Sankaril Pit 1 is dated to TF 851-4075 ± 100 and TF 850-2615 ± 100 B.P. for lower and upper layers respectively.

The paper describes a petrified osmundaceous rhizome discovered from near Bmdrabun m the Jurassic of the Rajmahal Hills, Bihar. The specimen made up of vertically growing leaf bases and roots, includes three stems in it. Each stem has a broad sclerenchymatous outer cortex, surrounding a narrow inner cortex. The stele consists of 50-70 individual strands arranged in a circle surrounding the sclerenchymatous pith. Most of the strands are continuous with one another. The medullary strands are absent. The C-shaped leaf traces are each enclosed in a sclerotid ring with several protoxylem groups. Several sclerenchymatous strands are found scattered in the pith of the trace as well as in the stipular wing. No sclerenchymatous tissue is noticed in contact with the stele of the leaf trace. The specimen differs from the other Jurassic species of Osmundites in the distribution of sclerenchymatous strands in the leaf bases.

The formation of Shola forest, the closed evergreen woods in the vicinity of Ootacamund in the Nilgiris in south India, commenced about 35,000 years ago through gradual invasion of the grasslands under a regime of low precipitation, absence of frost and high speed winds. The present disjunct distribution of the Shola forest is due to destruction of the forest probably by Man and much of the grasslands today seem due to anthropogenous activity.

Under the name Araucarites bindrabunensis sp. nov. two specimens of petrified araucarian megastrobili are described from the Raj mahal Hills. Bihar. The megastrobili are ellipsoid in form and bear closely arranged, numerous, single-seeded scales. The scales are ligulate, winged and woody. Vascular supply of the cone-scales is probably double. Sclereids are absent from the pith of the cone axis and resin cells from below the vascular bundles both in the scale and the ligule. Stomata are absent from the upper surface of the seed-scale. Epidermal cells vary in size and shape according to their position on the scale. In several respects the Rajmahal specimens resemble the fossil species Araucaria mirabilis (Speg.) Calder and the living species A. Bidwillii Hook.

The Pleistocene plant impressions from the Lower Karewas in Kashmir described by Middlemiss, Stewart and Puri are considered from the floristic and ecological viewpoints, in relation to stratigraphy and in the background of the events of the Pleistocene climatic and diastrophic changes. This attempt seeks to straighten out the facts and remove the confusion created by a similar consideration of this fossil flora by the earlier workers. From the stratigraphical considerations it is discovered that this flora came off from an upper part of the Lower Karewas (Lithozone 4) and is in no way representative of the vegetation of the entire Lower Karewas. Furthermore, the fossil flora is suggestive of temperate climate rather than tropical or subtropical as deduced by earlier workers. Comments are also made towards the application of this flora in determining the Plio-Pleistocene boundary in the Lower Karewas.

The paper reviews both the palynological and palaeobotanical evidences that have been put forward to suggest early domestication of plants in the Indian sub-continent, Thailand, Taiwan and China. It appears that the distinction between cereal and non-cereal pollen grains has been based upon insufficient data, and stages of the earliest occupation phase have not been judiciously inferred from the pollen diagrams. A careful sifting of all the evidences from India suggests that the domestication of plants commenced around 3,000 B.C. The alleged earliest records of domestication described from the Spirit Cave in Thailand and radio-carbon dated to 11,500 B.P., on scrutiny suggest a more advanced and discriminating stage in food-gathering, rather than domestication. This paper suggests a more detailed botanical identification of the plant remains and a careful evaluation of ethnographic information towards the inference of early domestication.

The paper describes the pollen statistics of ten primitive varieties of maize from Assam and Mexico. The pollen statistical data are used to recognize subfossil maize pollen from amongst the pollen of Cerealia recovered from the Postglacial deposits of Kashmir Valley. The evidences of subfossil pollen, the archaeobotanical material and the occurrence of most primitive types of maize in Assam seem to suggest the occurrence of maize in India during the Pre-Columbian time.

The paper discusses the extent of pollen production and variability in pollen morphology of Holoptelea integrifolia. Referring to the high incidence of its pollen in the atmosphere and its high allergenicity, the authors suggest that the practice of planting the trees of Holoptelea as graceful shade trees should be discontinued.

Forty-six types of spores and pollen grains have been described from the Nipania chert. They are classified in accordance with the classification suggested by Pant. Pteridophytic spores, cycadophytic pollen grains and the winged grains of the conifers are more or less equally represented in the microflora. Among the pteridophytic spores are some types resembling the spores of modern Lycopodium, Selaginella, Cyatheaceae and Schizaea. Megaspores are also described for the first time from the Jurassic rocks of India. The winged pollen includes two, three, and four-winged grains. Some new groups and sub-groups have been proposed in the classification suggested by Pant.

The Postglacial vegetational sequence revealed by the pollen diagrams constructed from the Haigam Lake, about 1,300 metres a.s.l., in the Kashmir Valley proper is divisible into eight vegetational stages. The vegetational history begins with Ash-elmalder-oak-wood phase and is followed by a conifer-mixed wood phase. With the amelioration of climate, a broad-leaved-conifer mixed forest is established. Probably in response to the worsening of climate or under the dual influence of climate and the biotic factor the oak-mixed wood declines and the pine woods are re-established. Evidences of the origin and the progressive development of agriculture during the Postglacial period are very convincingly brought out by the pollen diagrams. The earliest forest clearances took place in the conifer-mixed woods. The paper also discusses the correspondence between the progressive development of agricultural activity and the historical and archaeological evidences obtained in the valley. The pollen diagrams also present an interesting record of the occurrence of oaks, alder and elm in the valley proper which are absent from the valley today.

The atmosphere of Lucknow has been found highly charged with pollen grains and fungal spores during February, March, April and then September, October, November in the year 1969-70. There are considerable qualitative and quantitative differences in the pollen calendar prepared earlier by Lakhanpal and Nair (1958) and the pollen calendar of 1969-70. Pollen grains of Casuarina equisetifolia (2.4%), Ricinus communis (2.2%), Emblica officinalis (1.9%), Putranjiva roxbuyghii (1.4%), etc., were not recorded earlier. The shift in the flowering periods of Morus, Ailanthus and Azadirachta has been noted by a month. Long distance transport of Alnus pollen has been noticed in the months of September and October.

The paper describes several silicified pteridophytic remains, Lycoxylon indicum (SRIVASTAVA) emend., L. Type 2, Sphenopteris sp., Cladophlebis sahnii sp. nov., 5 types of petioles and rachises, 3 types of sori, 3 types of isolated sporangia, 2 new species of Solenostelopteris Kershaw (S. nipanica sp. nov. and S. sahnii sp. nov.), 3 new species of Dictyostelopteris gen. nov. (D. rajmahalense sp. nov., D. fasciosteloides sp. nov. and D. jacobi sp. nov.) and Tinpaharia sinuosa Jacob. In general composition the fossil flora of Nipania seems to compare with the fossil flora of Jabalpur and the Kota Stages of the Upper Gondwana and is, therefore, believed to belong to the uppermost strata in the Rajmahal Stage.

Besides adding additional information about the morphology of the already known silicified remains from Nipania, viz. Nipaniostrobus sahnii Rao, Masculostrobus rajmahalensis Rao, Nipanioruha granthia Rao, new material described includes Masculostrobus podocarpoides sp. nov., M. sp., Nipaniostrobus pagiophylloides sp. nov., N. aciculifolia sp. nov., Nipanioruha lanceolata sp. nov. and N. curvifolia sp. nov.; Mehtaia rajmahalensis gen. et sp. nov., M. nipaniensis sp. nov., M. santalensis sp. nov,; Sitholeya rajmahalensis gen. et sp. nov.; Indophyllum sahnii gen. et sp. nov., I. raoi sp. nov., I. nipanica sp. nov.; Elatocladus sahnii sp. nov., Brachyphyllum florini sp. nov.; Pagiophyllum araucaroides sp. nov. Fossil history of Podocarpaceae is also discussed.

Remains of food plants from the bottom layers of Neolithic horizon at Chirand near Patna, Bihar, comprise lentil, barley, rice, Pisum arvense, etc. These constitute the first record of Neolithic plant economy from North India. The Neolithic plant remains known from Burzahom in the Kashmir Valley are of weeds associated with cultivation. From a series of C14 dates at this site, it appears that the bottom layers are younger (405 B.C. - 1570 B.C.) than the overlying layers (1675-1750 B.C.). If no discrepancies arc involved, the bottom layers from which the plant remains have been discovered may be dated around 3000-4000 B.C.

Based on recent Pollen-analytical investigations of the Early and Late Quaternary deposits in the Kashmir Valley, the various aspects discussed include the background information regarding vegetation, the nature of the peat deposits, the present and past pollen rain, the parallelism in the course of vegetational development during the Late and Early Quaternary, the correlation of Postglacial pollen diagrams, the past altitudinal shifts in the vegetational belts, and the role of the climate vs biotic factor upon vegetational development.

The paper describes carbonized food grains and their impressions from Kaundinyapur a site in Madhya Pradesh. The remains include cereals (rice and ? maize), legumes (peas) and the fruit remain (jujube) and a crushed fragment of a bamboo. The various strata from which the material has been recovered range in age from 500 B.C. to 1400 A.D. representing slightly earlier Mauryan to the Muslim Period.

The paper presents result of pollen-analytical investigation at two sites in the middle altitude on the northern face of Pir Panjal. One of the sites, Yus Maidan, is a vast meadow surrounded by fir-blue pine forest and the other, the Baba Rishi swamp, is situated within the blue pine fir forest. The pollen diagrams from Yus Maidan reveal the encroachment of the forest at the site in the recent past whereas Baba Rishi site has been forested even before the origin of the swamp. Further, the pollen diagrams show that oaks existed as constituents of the forest and have been exterminated recently.

The paper describes a comparative account of pollen content and the megafossils in the Lower Karewa deposits at Ningle Nullah, Laredura, Dangarpur and Liddarmarg. At Ningle Nullah pollen analysis reveals dense Oak woods although not a single leaf impression of Quercus has been found in the megafossils. At Liddarmarg, Dangarpur and Laredura the dominance of Quercus among the leaf impression is not equally reflected in the pollen spectra. Conifers absent in the megafossils are represented by low frequencies. Members of Lauraceae, Rosaceae, Papilionaceae, Cornaceae, well represented among megafossils, are absent or poorly represented in pollen record. Trapa abundant in megafossils is either absent or extremely rare in pollen spectra. The paper emphasises the importance of both micro-and megafossil data in the reconstruction of past vegetation.

The paper describes results of the pollen analytical investigations carried out at the 'ox-bow' lake adjoining the archaeological site at Malvan, Gujarat. The pollen sequence reveals the pre- valence of open conditions with the vegetation consisting largely of grasses and Cheno-Amaranths along with several other herbaceous elements. The presence of low percentages of high pollen producers, such as of Holoptelea and Myrtaceae suggests the occurrence of distant arboreal vegetation. Microforaminifera of the coiled and biserial forms have been found in abundance in most samples. Their absence at certain depths suggests the intermittent occurrence of estuarine conditions in the' ox-bow' lake. The pollen sequence suggests hardly any change in climate. The pollen grains of Pinus, Cedrus, Alnus and Betula were incorporated in the sediments due to long distance transport from Himalaya or Baluchistan either by sea or by wind.

Under the name of Sahnia nipaniensis gen. et sp. nov. the author describes some specimens which he believes to be the male flowers of the Pentoxyleae. These were borne apically on dwarf shoots closely resembling those of Pentoxylon Sahnii Srivastava. The flower consists of filiform spirally branched microsporophylls, fused proximally to form a disc which surrounds a broad and conical receptacle. The unilocular sporangia are borne at the ends of short branches of the sporophylls. Pollen grains are monocolpate and boat-shaped. In young flower the microsporophylls are surrounded by a whorl of deciduous bracts. The infructescence of Carnoconites laxum and several specimens (showing longitudinal section) of the infructescence of C. compactum have also been discovered. The infructescence of C. laxum differs from that of C. compactum in having much shorter pedicels and much longer female cones. The infructescence of C. compactum differs from the reconstruction made by Professor Sahni in the absence of bifurcation of the pedicels and in the arrangement of the cones.

The remains of husk and chaff in the terracotta cakes from the Harappan site, Kalibangan, earlier reported by Sarma (1972) as those of rice (Oryza sp.), have on cuticular examination been found to belong to wheat (Triticum sp.).

NA

Under the name Sporojuglandoidites jurassicus a new sporomorph is described from the Jurassic rocks of India. The sporomorph is distinguished by the presence of foraminoid apertures on its body-a character not met with in any plant group except the angiosperms. In general characters it seems to resemble the juglandoid grains.