AASP Primary Records Program

Amiya Kumar Ghosh

• Sharma, Mitra and Banerjee, 1984
• Sunirmal Chanda, 1985
• Satish Srivastava, 2003

THE FOLLOWING BIOGRAPHY PUBLISHED IN THE FOLLOWING REFERENCE WAS RECEIVED THROUGH THE COURTESY OF PROFESSOR MANJU BANERJEE, UNIVERSITY OF CALCUTTA, KOLKATTA, INDIA, IN RESPONSE TO A REQUEST BY SATISH K. SRIVASTAVA.

1984 In: Evolutionary Botany and Biostratigraphy; A. K. Ghosh Commemoration Volume (eds.: A. K. Sharma, G. C. Mitra and M. Banerjee) (Current Trends in Life Sciences, vol. 10, 694 pages): Today and Tomorrow's Printers, New Delhi, India.

In the case of Prof. Ghosh his contact with palaeobotany started in 1941 with the investigation of fossil pollen obtained from the maceration of a Tertiary carbonaceous shale from Laitringew near Cherrapunji, then in Assam, but now in the State of Meghalaya. Thus began his evergrowing interest in the study of microfossils which was later to be known as "Palaeopalynology". With his educational background of both botany and ecology, he was ideally suited for this discipline.

The study of Tertiary pollen from Assam was followed by an investigation of Late Tertiary diatomaceous earth from the Nicobar Islands. The short descriptions and the detailed drawings of the important diatom genera obtained from this earth illustrate the keenness of observation displayed by Prof. Ghosh. This was a pioneer work on the fossil diatoms of India published in 1947.

In quick succession came two investigations on the microfossils obtained from Indian coal seams. The first, carried out jointly with Chandiok and J. Sen, concerned the microflora of Chope coalfield, near Hazaribagh, Bihar, recovered from a seam considered to be Barakar in age. The fossil spores were described as different types and their percentage were plotted on a frequency diagram according to the method then adopted by Raistrick. The second investigation was more detailed. Made in collaboration with J. Sen it comprises the study of the microfossils and the correlation of some productive coal seams of the Raniganj Coalfield, Bengal. This can be rated as the second major palaepopalynological study from India, the first being the work on spores from the Lower Gondwanas of India and Australia by Dr. C. Virkki (Later Mrs. Jacob) published in 1945. Ghosh and Sen's study furnished a proof of the usefulness of plant microfossils in the correlation of coal seams in those early days. About 52 spore types, 11 types of wood fragments, 31 cuticular types and 8 unknown plant fragments interesting both from correlative and palaeobotanical points of view were described and discussed. The evidence of microfloral assemblage was also regarded to indicate a warm, moist and uniform climate prevailing during the formation of these coal seams.

As a sequel and elaboration of the above study Prof. Ghosh in 1953 pointed out a paper entitled "Recent advances on palaeobotany of coal and their application to the scientific and technological utilization of coal" that besides the application of microfossils in the correlation of coal seams, coal palaeobotany has other economic application like determining the nature of coal, determination of horizons and genetic age of the coal, exploration of a known seam is an unknown area across a fault and also amount of crushing necessary from different coal after extraction.

In the mid- 1940s there was a lively controversy about the age of the saline series of the Punjab salt range. On the basis of field evidence, geologists like Gee and Fox regarded it as Cambrian and Pre-Cambrian. But on the basis of the microfossils comprising Shreds of gymnospermous and angiospermous woods, cuticle of grasses, etc., obtained from Saline Series by macerating, Prof. B. Sahni regarded it as Eocene. His contension was that angiospermous remains could not have occurred earlier than the Tertiary. To strengthen his argument he cited the absence of vascular elements in the Cambrian strata of the Salt Range which he said were unconformably lying over the Saline Series. Prof. Ghosh and his associates checked the results obtained by Prof. Sahni and his collaborators and found the occurrence of vascular elements even in the Cambrian rocks.

The controversy over the age of the saline Series could not be resolved due to the sudden demise of Prof. Sahni in1949. But it inspired Prof. Ghosh to further investigate whether vascular plants existed in Cambrian times or not. To collect sufficient evidences, he and A. Bose, his main associate in this study, investigated Cambrian rocks of Punjab Salt Range and Kashmir, Pre-Cambrian rocks of Dharwar and Cuddapah, some Vindhyan rocks and a few Cambrian specimens from North America. From these rocks they obtained wood elements and monolete and trilete types of spores, leading to the conclusion of the fact that their findings were not in agreement with the view of the majority of investigators who did not consider vascular plants to have existed in Pre-Silurian times. Still they had the courage to stand by their own observations, which were also supported by the works of Naumova, Reissinger and Kopeliovitch in Europe and Jacob and his associates in India. In 1969 they again published a paper on the spores of vascular plants obtained from nine samples of Cambrain rocks of North America, further reiterating the existence of vascular plants in the Cambrian.

Prof. Ghosh's investigations related with the occurrence of earliest vascular plant led him to have a more critical looks to at all the organic remains reported from Pre-Cambrian deposits. This formed the subject matter of the 43rd Acharya Jagadis Chandra Bose endowment lecture which he delivered in November 1973 under the title "Life in the Proterozoic".

In 1956 Prof. Ghosh joined the Oil and Natural Gas Commission and established a palynological laboratory at Dehra Dun. For nearly the next decade his publications were mainly, though not exclusively, in the domain of palaeopalynology with a bearing on stratigraphy. Among them the more noteworthy are two papers on pteridophytic spores with D.Banerjee, on polycolpate grains with S.K.Srivastava and one on Mesozoic Polospores with N.G.Lukose . All these 4 papers were presented at the first International Palynological conference at Tucson in 1968 and had significant value from the palynostratigraphic viewpoint.

Of the two papers on pteridophytic spores, the first dealt with all types except Parkeriaceae and Schizaeaceae, from the Tertiary of Assam. It described a large number and variety of spores recovered from Eocene to Pliocene sediments, classified according to the scheme proposed by Van der Hammen. The range of occurrence and relative frequency of the different sub genera and species had also been discussed. Some of them are useful as marker types for correlation purposes.

The other paper dealing with the Parkeriaceae and Schizaeaceae described 8 types of Schizaea, 3 types of Lygodium, 4 types of Anemia, 1 type of Mohria and 2 types of Ceratopteris from the Mesozoic and Tertiary sediments of India. Of these spores, Ceratopteris sp. were found to be characteristic of Miocene, being rare in Oliogocene and absent in Eocene. Mohria sp. were found in the Lower and Middle Miocene. Schizaea spores although occurring from Jurassic to Lower Miocene were better represented during the Miocene.

Palynological examination of different samples of various horizons from eastern and south western India by Ghosh and his associates and ONGC revealed that round grains bearing 4 to 11 colpi, scabrate exine having reticulate ornamentation were restricted in Pre-Miocene horizons. They showed comparison with the grains described by Potonie' as Nothofagidites from the Eocene of Burma. A significant phenomenon was observed that the frequency of grains with more colpi increased with the older horizons of the Pre-Miocene formations.

The 4th paper gave well illustrated accounts of 15 types of dispersed spores and pollen grains from a few Jurassic - Cretaceous samples of North-Western India.

Prof. Ghosh published two comprehensive papers on the role of palynology in oil exploration and one dealing with palynology in relation to stratigraphy in general. Two of his addresses were devoted to special areas of palynology. In the 8th Annual Lecture to the Palynological Society of India delivered in 1973, he dealt with the palynology of the Gondwanas. Later, in his address as a chairman at the first Indian Palynological Congress at Chandigarh (published in 1977) he spoke about the palynology of the Siwaliks.

In the Autumn School in Palaeobotany held at Kodaikanal in 1972 he and Urmila Deb gave an excellent review of the cryptogamic spores from the Tertiary of India and their bearing on stratigraphy, which formed a chapter in "Aspects and Appraisal of Indian Palaeobotany", published by Birbal Sahni Institute of Palaeobotany.

The famous French wit, Maurice Chevalier is reported to have remarked that it is safe and proper to keep to the main high way but once in a while there is no harm in going in to the side alleys too as it adds flavour to the journey. For Prof. Ghosh palaeopalynology was the main high way but at times he also persued enquiries into other branches of palaeobotany. For example, during his tenure at the ONGC he described two Tertiary fossil woods; Anisopteroxylon jawalamukhi from Siwaliks of Himachal Pradesh and Dipterocarpoxylon malavii from the Pliocene of Kutch. After returning from ONGC he in collaboration with A. K. Pal, reported the occurrence of two fossil algae from the Bagh Beds of Madhya Pradesh.

In 1973, jointly with Manju Banerjee he published "Further studies on the genus Glossopteris Sternb. and its stratigraphic significance". Then in 1974 came out another of his papers based on megafossil materials, in joint authorship with Urmila Deb, reporting the occurrence of Terminalioxylon, and angiospermous fossil wood in the Tertiary deposits near Bolpur, West Bengal.

Back in Calcutta he devoted more and more time to teaching and guiding research in palaeobotany. Along with the basic knowledge, he keenly followed the recent developments in Palaeobotany by keeping in touch with the latest literature. This was reflected in his presidential addresses to the Botanical Society of Bengal from 1969 to 1971. Similarly, in 1972, he reviewed the progress of palaeobotany from 1963 to 1972 in the publication entitled "Decade of science in India".

His last such review was on "Growth of Palaeobotany in relation to biostratigraphy of India" which he delivered as the 26th Sir Albert Charles Seward Memorial Lecture at the Birbal Sahni Institute of Palaobotany in November 1978.

This is by no means is an exhaustive treatment of the entire palaeobotanical work of Prof. A. K. Ghosh but only a brief resume which I have presented on this auspicious occasion when he have all gathered here to honour a great teacher and a devoted scientist.

This remembrance was provided by Satish Srivastava, October, 2003.

Mr. A. K. Ghosh was registrar at the Bose Research Institute, Calcutta, before his appointment in the ONGC as Palynologist (Sr.) in 1956 and in-charge of the Palynology Laboratory. He was about 53 yrs age. He worked intensely on the palynology of the Vindhyan Series. The age of the Upper Vindhyans is controversial but generally believed as basal Cambrian. They are correlated with the Salt Range Cambrian strata of western Himalayas in Kashmir. Once Ghosh told me that his thesis on the plant remains in Vindhyans completed under the supervision of Professor S. P. Agharkar at Calcutta University was adversely criticized by Professor Birbal Sahni of Lucknow University, who had worked on the Salt Range and was an external examiner for his thesis. Criticism was directed to Ghosh's supervisor for the thesis. Ghosh never resubmitted thesis but worked on Vindhyans most of his life. The presence of fragmentary vascular plant microfossils of the Vindhyans and their correlation with Salt Range could never be reconciled. Thus, Ghosh came in direct controversy with Birbal Sahni whose viewpoints contradicted Ghosh's. The controversy received global attention and Ghosh became known as "Cambrian Ghosh" worldwide.

On his retirement from ONGC in 1962, Ghosh became an emeritus professor in the Botany Department of Calcutta University where he advised several palynology students, e.g., Manju Sharma, A. Nandi.

Ghosh had a knack of indulging in controversial problems. He wanted to produce results where others failed. The Krols, exposed as a belt of nappes from east to west in the Himalayas, had tantalized several paleontologists but produced frustratingly few results. In 1959, Ghosh, A. T. R. Raju (an ONGC field geologist-petrologist), and I (Satish Srivastava) collected Precambrian to Jurassic samples, including the Krols, from exposures along a mule-track between Dehradun and Mussoorie. This gave me my first taste of field geology. In 1962, Ghosh and I co-authored a paper on the palynology of Krols beds exposed on this tract.