NA TURE 



5^7 



THURSDAY, SEPTEMBER 26, i{ 



THE TERTIARY FLORA OF AUSTRALIA. 



Contributions to the Tertiary Flora of Australia. By 

 C. von Ettingshausen. Memoirs of the Geological 

 Survey of New South Wales. (Sydney : Charles 

 Potter, 1888.) 



THE work consists of translations from the German 

 originals of two memoirs, published respectively in 

 1883 and 1886, with explanatory notes on the geology by 

 the Survey officers. Ettingshausen's contribution consists 

 of about 170 pages of "exact determinations of fossils" 

 and a few pages of theoretical considerations and tabu- 

 lated lists. In these we are informed that the "Tertiary 

 floras " formed one universal flora, which spread over all 

 lands outside the tropics, and " that in this flora all the 

 elements of the different floras of the world are found 

 combined "(p. 3). The " Tertiary period," from this point 

 of view, consists of sub-periods of uniform conditions, 

 susceptible of exact classification and correlation, with 

 an orderly beginning and definite close. From another 

 point of view it is a period of the world's history, so 

 stupendous, so broken and diversified, that we can never 

 hope to reconstruct a complete history from its imperfect 

 records, and to marshal its secrets into exact order. 

 Embraced in its vast folds are sediments, perhaps coasval 

 with our chalk, beginning when much that is now land 

 was the abyssal depths of ocean, and enduring while 

 continents and seas slowly changed their places. Its 

 episodes were the joining hands of widely severed lands 

 and the parting of them again asunder into isolated 

 tracts, until at last it saw the existing continents settling 

 into their present form. So enormous was its duration, 

 that its " newer" periods sufficed to raise and scarp the 

 loftiest mountain ranges of the world ; and its close to 

 submerge and re-elevate again and again, to trim, alter, 

 and finally cut into separate islands the insignificant por- 

 tion of the globe we inhabit as Great Britain. During 

 all which time, floras as distinctive as any of those now 

 existing were swayed hither and thither by the changing 

 cHmatic conditions accompanying the oscillations of land 

 and water — here picking up recruits on their passage, and 

 there deserted by the worn out; here coalescing with dis- 

 tinct hosts who struggled and thinned, or swelled, each 

 other's ranks, and there dwindling in numbers as stations 

 or habitats became submerged and broken up. As well j 

 might we try to arrive at a complete history of the feuds 

 and migrations of Palseolithic man, as of the floras of 

 the " Tertiary period," for at most each country can but 1 

 contribute a few isolated facts regarding the floras that ! 

 have passed over it. Thus, though we possess a broken 1 

 record in the Isle of Wight of 3000 feet of Tertiaries, mostly 

 deposited under conditions extremely favourable to the 

 preservation of plants, this has, in the island, yielded an 

 adequate idea of its forest vegetation for about 6 inches 

 of its thickness. Nevertheless, remains of floras are 

 repeatedly sandwiched in our Eocenes. These begin 

 abruptly, with nothing leading up to them ; and if we go 

 to Ireland and Scotland we can supplement them with 

 Vol. XL.— No. 1039. 



I other 3000 feet of volcanic rocks with still older floras 

 1 sandwiched among them, but affording no beginning 

 i to the "Tertiary formation." And our series ends 

 abruptly, leaving an enormous gap of most critical time 

 j unrepresented between Oligocene and Pliocene, yet 

 having revealed flora after flora as utterly distinct from 

 each other as those of the antipodes, and with scarce 

 any elements in common. Thus, however such condi- 

 tions may have obtained in Carboniferous times, this 

 theory of a uniform flora or fauna spreading, during the 

 Tertiaries, over both hemispheres, from the limits of 

 \ vegetation to the confines of the tropics, is altogether 

 outside practical science, and simply leads to affinities 

 being discovered between imperfectly preserved common 

 types of vegetable organisms, where none such perhaps 

 exist. 



With regard to the 170 pages of " exact determinations 

 ; of fossils," though no species-makers are so prolific as 

 palaso-phytologists, our author certainly bids fair to beat 

 the record, for sp. nov. is attached to as many of the 

 fragments as the limits of the collection would well allow. 

 The three ferns and three monocotyledons are negative, 

 if unsatisfactory, but there would have been one less 

 belonging "undoubtedly to the Monocotyledones," had 

 not a stray Carboniferous specimen been included in the 

 consignment. The single Cycad is a sp. nov., bearing 

 " a remarkable and specific relation " to a North Green- 

 land fossil. The Coniferse are determined on very poor 

 material, but most are considered as at least allied to 

 Australian forms ; yet Sequoia is imported when the 

 native Athrotaxis would better meet the case. A new 

 genus, Heterocladiscos, is actually founded on some insig- 

 nificant cupressineous foliage only, and another, Pseiido- 

 pinus, is certainly curious if its supposed fruits are cones 

 and not catkins. Of the some 150 new dicotyledons, the 

 vast bulk would be classed as indeterminable fragments 

 by any reasonably cautious palaeontologist. The less 

 characterized of these figure as the exotics to Australia, 

 whilst the most satisfactory are found among the Pro- 

 teaceae and other Australian forms as Boronia, Euca- 

 lyptus, species of Piper, Ceratopetaliim, &c. Many of the 

 species are founded on single fragments, sometimes with- 

 out base or tip, and unless the plates do them injustice, 

 with scarcely any visible venation or character. 



We cannot judge of the difficulties of collecting, but it 

 certainly appears that if it is worth while to publish any- 

 thing on fossil plants at the Government expense, it would 

 be worth while to gather proper material for it. When 

 broken specimens of leaves are obtainable, entire ones 

 can as a rule be extracted, and when these are to hand, 

 though exotic genera may well have flourished in Aus- 

 tralia as in Europe in bygone ages, it will be surprising if 

 more of them cannot be matched with plants nearer their 

 own home. J. Starkie Gardner. 



OUR BOOK SHELF. 



Useful Rules and Tables. By William J. M. Rankine. 

 Seventh Edition, revised by W. J. Millar, C.E. (Lon- 

 don : C. Griffin and Co., 1889.) 



This is the seventh edition of a work which at the 

 present day is almost indispensable to engineers in 

 general. The increase and development of mathematics, 



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