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In 1864, Sclater proposed a Tertiary continent connecting Africa, Madagascar, and the Mascarene Islands, off of the southwest coast of India, to explain the distribution of small mammals. His ‘Lemuria’ was superseded among biogeographers by Wallace's land bridges in 1876. The notion of an ancient continent of Gondwána-Land had a different intellectual lineage. It grew as a paleogeographical idea from the fieldwork and paleontological studies of the Geological Survey of India (GSI) in the 1850s, 1860s, and 1870s and proved to be durable, albeit with different configurations, over the last century and a half. Initially, the Gondwána rocks were termed Raniganj Series, Talchir Series, and so on, after the great coalfields in India, but in the 1870s they were consolidated into the Gondwána Series and then Gondwána System. At the same time, the GSI scientists posited a continent of Gondwána age rocks stretching from Africa across India and on to Australia. In 1885, Suess proposed a more limited Gondwánan-aged Indo-African continent, mostly similar to Sclater's Lemuria, which he named Gondwána-Land. Suess's construct also included a tectonic component that the GSI's landmass did not. But it was not the vast continent in terms of its size that the GSI people had envisioned, which, in time, Suess would also acknowledge. In 1890, William Blanford, a central figure in the GSI part of the Gondwána story, reviewed and expanded the concept of the continent to South America, based on Neumayr's 1887 work, and suggested an Antarctica involvement. Curiously, however, some historians and geologists have overlooked the work that preceded Suess and have credited Suess with the entire idea.

During the Late Devonian, in what is now northcentral Pennsylvania, slow moving streams meandered across the plain of the "Catskill" Delta. A varied fish fauna lived in these streams, and their remains are entombed in the ancient stream channel and floodplain sediments. In the 1830's, English railroad engineer Richard Cowling Taylor visited the coal mining community of Blossburg and remarked on the analogy between the Old Red Sandstone of England and that found near Blossburg. Not long afterwards, James Hall (1811-1898), best known for his work on Paleozoic invertebrates of New York, also visited Blossburg to clear up vexing boundary problems in the New York formations. He obtained fish scales from the red sandstones, many of which he identified as scales of Holoptychus nobilissimus, a crossopterygian fish described by Louis Agassiz in 1839. In his annual report for 1839 to the New York Legislature, Hall also took note of some large scales, which were unlike any previously described. Under pressure from the Governor, Hall, like the other survey scientists, had to submit timely reports even if studies were incomplete, and he hurriedly described the new scales, referring them to a new genus and species, Sauritolepis taylori. In his final survey report (1843). Hall dealt more fully with the new fish, renaming it Sauripteris taylori based on the fin structure, the significance of which he had not earlier recognized. The Blossburg fishes did not languish in obscurity; James DeKay referred to them in his checklist of fishes of New York, as did Charles Lyell in his 1845 Travels in North America. In 1890 John Strong Newberry placed the fish fossils in the Lower Carboniferous; he also described several new species. Hall's handling of the fossil fish he had before him and, indeed, the reasons for entering Pennsylvania in the first place, are emblematic of the way much science was practiced in the first half of the 19th century. Further, recent field work in the Blossburg area shows Hall's astuteness as a field geologist for he correctly placed the fish in the Upper Devonian, although in this region the Upper Devonian-Lower Carboniferous boundary is not well defined.

In 1850 Philip Thomas Tyson observed that earthquakes of great energy must have occurred in very recent geological periods in the Coast Range of California. A few years later, in 1856, Dr. John Boardman Trask, San Francisco physician, California's first unofficial state geologist, and a founder of the California Academy of Natural Sciences, began to compile data on California quakes. His first contribution to seismology was a summary paper on California earthquakes from 1812 to 1855, which was followed by annual compilations on earthquake activity through 1865. Trask's papers were read at meetings of the California Academy of Natural Sciences and were published in the Proceedings of the Academy. Trask made a determination of the probable direction of motion and velocity of several earthquakes by the imaginative use of the telegraph and other means of communication. After 1866 Trask pursued other interests, and the Academy's concern for earthquakes waned. In the 1880s the center for earthquake studies shifted to the University of California at Berkeley. Edward Singleton Holden, President of the University, in 1887 published the first comprehensive catalog of California earthquakes, and subsequently revived the annual compilations. More importantly, in the same year, Holden established at the University the first seismographic stations in the Western Hemisphere, one at Berkeley, and one at the University's new Lick Observatory on Mount Hamilton, near San Jose. Although this marks the beginning of the modern period of California earthquake studies, it was the disastrous San Francisco earthquake of April, 1906 that rattled the complacent public and scientific communities alike and launched a new era of seismology.

Wegener's hypothesis was introduced to Britain in 1922. First heralded as a revolution in thought, possibly comparable with that initiated by Copernicus, it was quickly attacked as groundless speculation, negating all known facts about the thickness and solidity of the earth's crust. As advocates and opponents joined the battle, some British scientists saw how it could help to solve geological problems and adopted a cautiously favorable attitude toward Wegener's basic idea of continental motion, although they disputed the details. In 1928, a British geologist proposed convection currents as the mechanism for splitting continents and rafting apart the fragments, thus providing a crucial element to the model that, decades later, would aid in the transformation of continental drift to plate tectonics. At the time of Wegener's death in 1930, his hypothesis remained under strong attack, yet support was well-established among Britain's independently-minded scientists.

The uncertain relationship of plate tectonics and biogeography is but the most recent chapter of a history of geoteetonics and biogeography which extends back to the middle of the last century. This history is largely unknown to Anglophone earth scientists, since most of it unfolded in Germany, Switzerland, France and Austria-Hungary. An outline sketch of this history is offered.

Darwin's South American fossil collections yielded many insights. in one section he recorded the gradual vertical change in shell characteristics of fossil oysters. The giant fossil vertebrates brought the realization that several were precursors of living species. Contrary to accepted Catastrophism Theory, he inferred that all taxa found fossilized did not become extinct together since the living agouti, among others, had fossil precursors. He envisioned the way an existing molluscan fauna and its sedimentary matrix could be transformed into fossiliferous rocks reminiscent of the Tertiary, and also speculated about the kinds of fossils that the Galapagos biota would yield in some future rock column. Volcanic islands (Galapagos Archipelago and others) were linked in Darwin's thought to the appearance of "peculiar" taxa inhabiting these "mere spots" in the sea. Were these migrants from the nearest continents? If so, why were they so distinctive while carrying the imprint of their place of origin? If not, how did these four-legged and other terrestrial creatures get to the islands? Were the archipelagos ever united to the continents? Gradually Darwin was led to a continent-archipelago-continent concept. Continents were elevated archipelagos. (He had the Andean volcanoes in mind.) Archipelagos were submerged remnants of continents. He incorporated into this concept the rise and extinction of species: elevation of archipelagos were the "best nurseries" for appearance of new taxa, while subsidence of continents generally led to extinction of extant forms.

According to Croizat's global synthesis, the main biogeographic patterns include trans-Atlantic, trans-Pacific, trans-Indoceanic, Boreal, and Austral. Geological and geophysical theories vary, but agree that sea-floor spreading in the Pacific is different in its effect from that in other ocean basins. The difference allows for radial expansion of the basin and not merely east-west displacement of continental areas. Biogeographic data suggest that bipolar (boreal + austral) distributions are to be reckoned among the results of sea-floor spreading in the Pacific. Data from one group of inshore fishes (family Engraulidae) exemplify this notion and add, as terminal parts of the differentiation of the Pacific Basin, trans-Panama marine vicariance and a collateral occurrence in freshwater of tropical South America. These findings corroborate Croizat's synthesis. They suggest that the critical evaluation of that synthesis will be the main task of biogeography over the next decade. They indicate that within the area of systematics, evaluation will require a cladistic approach and the elimination of paraphyletic groups from classification.

This paper examines the biogeographical component of the sixty-year controversy over the reality of continental drift. It begins with an examination of Wegener's solution to the problem of accounting for the distribution of life forms having a geographically disjunctive distribution and traces the development of the problem through the work of the major as well as many minor participants in the controversy. It closes with a discussion of the most important impact of the acceptance of plate tectonics upon the biogeographical community, namely, the rise of meta-biogeography.

The reaction in Germany indicates that in spite of World War I, the geological community was very much alive. Opinions ranged from violent and emotional rejections by prominent scientists, who saw their previously published theories challenged, to active acceptance of an exciting new concept to be tested in the various fields of geology. The French reaction, delayed by the death of many geologists during the war, and hampered by the language barrier, remained provincial and chauvinistic. Only lofty and skeptical comments were presented against what was considered an amateurish theory by a geophysicist. In reality, nobody in France, with the exception of Philibert Russo and Boris Choubert, was at the time involved in any orogenic theory or prepared to accept the challenge. The idea of continental bridges prevailed. In Switzerland, after the introduction of Wegener's ideas by Emile Argand during the war, and in spite of strong anti-German feelings, the concept was accepted quickly and enthusiastically as the best framework for solving critical problems of Alpine tectonics. Several famous Austrian geologists had published orogenic theories for the Alps based on the contraction the-ory and rejected Wegener's mobilism, but later, under the influence of Swiss geologists, they showed partial acceptance. Belgian geologists rejected Wegener's theory because they considered the beautiful symmetry of the present surface of the Earth incompatible with the assumed breaking-up of an original continental mass. Italian geologists, with a few exceptions, rejected Wegener's "aberration" while Spain, unaffected by the war, had a positive attitude which was facilitated by an early translation and a receptive academic audience. Dutch geologists, deeply involved with the Indonesian archipelago, accepted widespread mobilism with enthusiasm since it provided a spectacular answer to their problems. The Scandinavians, supportive but unable to interpret Precambrian geology with Wegener's theory, concentrated their efforts on astronomical and geodetic studies of present-day drift in the Arctic region. In summary, the reaction in Continental Europe was extremely diversified and dominated by an association of strong post World War I politics, the language barrier, the stifling of academic authority, passions of individuals, and regionalism of geology.

Hall's career with New York State was as stormy as his relations with many of his disciples. A few years after completing his education with Amos Eaton at Rensselaer Polytechnic Institute, Hall served during 1836-1837 as Ebenezer Emmons' assistant on the New York State Natural History Survey, working on the iron ores of the Adirondacks. From 1837 to 1842, Hall was the survey geologist assigned the western counties of the state. He contributed equally with the other geologists to the creation of the New York System for Paleozoic rocks; it is important, in focusing on Hall, not to lose sight of what the others provided to its development. Hall's final district report, published in 1843, evidenced his ability and interest in paleontology. The state hired him to research and write up New York's fossils, an assignment given in 1837 to Timothy Conrad, who had not completed the report. Hall was to spend the next several decades on the task, issuing thirteen sumptuously illustrated volumes. Through 1859, Hall took the fossils in stratigraphic order, but by 1867 he had switched to a biological approach, in part because by that time he had reached the rich and complex Devonian fauna. State support for the Palaeontology was uneven; in 1850-55, Hall worked without salary on the books. He used the reports to discuss other important geological topics and to air his position on geological controversies, some of them centered on rocks outside of New York. His parade of laboratory and field assistants helped in various degrees, sometimes with stinting acknowledgment from Hall. His international reputation was based in large part on his work for New York State, and it remains a durable legacy to science.