In his critique of the hypothesis of continental drift, V. Oppenheim (1967) discusses very briefly the Antarctic continent and concludes that "^hellip the geological and geophysical information gathered to date indicates that the Antarctic continent evolved and grew by accretions^hellip" and that "^hellip there is no evidence of the effect of a hypothetical continental drift anywhere in this part of the Pacific basin."

The information used by Oppenheim to arrive at this conclusion either has been missed inadvertently or obscured for inexplicable reasons considering his extensive work in South America. No mention is made of the recent and most significant discoveries made during Antarctic expeditions in the past decade, which contributed to the revival of the hypothesis of continental drift. There is much information available and evidence accumulated which present the "drifters" as well as the "nondrifters" with an unavoidable challenge and food for serious thought.

In the scheme of the jigsaw puzzle of Gondwanaland, Antarctica occupies a key position which, until the discovery of the Ohio Range stratigraphic section, initially had been vague and later a matter of hypothetical speculation. Any hypothesis would require geological continuity through Antarctica, particularly in the stratigraphic succession. Structural hypotheses are as vulnerable as the final hypothesis of drift itself, but when field evidence is presented in the form of rock and fossil specimens which one can hold in his hands and view carefully with his eyes, then some sort of explanation becomes essential.

Du Toit's (1927) comparison between the stratigraphic successions of South America and South Africa made it obvious that, if the jigsaw puzzle were to be complete, then Antarctica probably should have a similar, if not altogether identical, stratigraphic succession for the "Gondwana" time span, particularly the presence of a tillite. I had the fortune of participating in the discovery of the classical "Gondwana" section in the Ohio Range, Antarctica, complete with its Devonian fossils (Doumani et al., 1965), the Buckeye Tillite (Long, 1965), the coal seams and the typical Glossopteris flora in the coal measures (Schopf, 1962; Cridland, 1963), the leaiid conchostracans (Doumani and Tasch, 1963, 1965), and the ubiquitous diabase sills capping the whole section.

In the Antarctic Devonian strata, the faunas are so similar to their South African and South American counterparts that, except for their geographic location, they could be the same species. In the description of the fauna, we presented all pertinent arguments concerning their correlation. I had concluded that the elements of the Horlick Formation fauna of the Ohio Range are related closely to those of other Southern Hemisphere Devonian communities, and the assemblage as a whole is considered to be an integral part of the Malvinokaffric fauna of that age. Even to the smallest detail--such as the absence of cephalopods, the paucity of aviculids and pterineids, the concentration of spiriferids on bedding planes, the absence of limestone, and the presence of a coarse basal sandstone and alcareous concretions--the characteristics are identical in the separate continents. This unusual match in three presently distant places cannot be dismissed as merely coincidental.

It is difficult to explain the presence of identical brachiopods, for example, at the same time in their geological past and in the same position relative to the general stratigraphic succession, in places separated by thousands of miles of ocean water. Brachiopod larvae are in the floating stage

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for a few hours only, perhaps a week or two at the most, after which they settle to the bottom to become sessile benthos. Oceanic deeps are doubtless an unsurmountable barrier against their migration, which leaves us with the unanswered question: how did they get there? The same question applies to the other members of this faunal assemblage, namely the Tentaculites, bryozoans, gastropods, pelecypods, trilobites, and the psylophitic plants.

Above the Devonian is a sequence of glacial deposits, also in the same relative position as in each of the other Southern Hemisphere continents. The Buckeye Tillite of the Ohio Range subsequently has been found to be of regional dimensions, which rules out the argument for local glaciations. How, then, could the South Pole have existed during the same geologic period in different continents as they are now? If the continents were not close to each other, did the earth have more than one south pole at the same time?

The Glossopteris elements in the coal measures are striking. One does not have to be a geologist to raise the eyebrows in wonderment and feel befuddled at the sight of fossil trees 2 ft in diameter, leaves more than 1 ft long, and coal seams about 25 ft thick, all within 3° of the South Pole (Doumani and Minshew, 1964, 1965).

This lush vegetation occurs in an area of more than 5½ million sq mi covered with ice about 2 mi thick. The highest temperature which I recorded near Mount Howe (earth's southernmost mountain) was -15°C, for two hours only in midsummer; the mean monthly temperature at the nearby South Pole ranges from -25° to -62°C (Rubin, 1962), and the high East Antarctic plateau is cloaked in a 1,000-ft veneer of cold air for more than 80 percent of the year (Sabbagh, 1963). The countless glaciological and meteorological measurements in Antarctica show that its meager precipitation makes the continent a typical arid region. However, regardless of precipitation, the maintenance of below-freezing temperatures throughout the year eliminates the prevalence of moisture which is essen ial for life.

The proponents of static continental masses growing by accretion in the same place, under the same physical conditions, have no alternative now but to modify, or abandon, their views in quest for a convincing explanation. The evidence indubitably indicates that these Antarctic rocks under no conceivable circumstances were deposited at these latitudes.

Conceding the argument of plant seed and pollen transport by wind or water, birds having not evolved yet at that time, we are confronted with the problem of fresh-water animals. I collected leaiid conchostracans from the Ohio Range coal measures, where they occur in association with the Glossopteris flora, in strata with very sharp vertical restrictions. Almost identical species are present in the same relative strata in South America, South Africa, and Australia, similarly associated with Glossopteris elements, and similarly restricted in their vertical ranges.

Coincidence here is hardly convincing. These leaiids are fresh-water animals whose eggs, though transportable by wind in their dry state, are perishable readily in ocean water. Now, the question arises: how could these identical animals have existed in small, fresh-water puddles, in identical relative positions in the stratigraphic succession, and during the same period of time, in several places on the face of this earth, separated by thousands of miles of ocean water? A similar example is presented for the small lizard, Mesosaurus, which occurs in Southern Hemisphere continents under equal depositional conditions. Although my arduous search for the elusive little lizard has been a failure, I believe that the presence of Mesosaurus in Antarctica is likely.

The evidence for closeness and proximity of Antarctica and the other Southern Hemisphere continents is compelling. At this time, the hypothesis of continental drift appears to provide the most convenient explanation. Our ignorance of a logical mechanism by which such a drift could be initiated and perpetrated is a poor excuse for rejecting the hypothesis. The field geologist collects the tangible evidence, and it is up to the physicist and the expert in mechanics to try to find the acceptable mechanism.

In his conclusion, Oppenheim seems to favor expansion rather than drift, which may account for previous proximity. However, this would keep Antarctica where it is now throughout its geologic history. This is difficult to accept, for one still would have to present an acceptable thesis on how lush vegetation could have flourished in a place now covered with a thick ice sheet.

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