Bibliographical Notices. Gl 



and it m;iy be taken conclusively that no direct evidence is afforded 

 in favour of the existence of climatal zones in Carboniferous and 

 Jurassic times. 



The Tertiary Arctic plants were regarded as Miocene by Heer ; 

 but J. S. Gardner has adduced reasons to prove that they show a 

 passage from the Cretaceous to the Miocene, and that therefore 

 they may claim to be Eocene. 



The difficulty of regarding the plants of the old Coal-measures as 

 definite indie itors of climate is carefully dwelt upon. Their several 

 structures and relative size cannot be taken without great caution 

 as indications of a tropical climate, nor of the presence of an excess 

 of carbonic acid in the air ; nor iudeel would a hot climate suit 

 the peat-like decomposition of marsh-jjlants. Certainly the coal- 

 plants had a very wide geographical distribution, favoured by ( 1 ) the 

 absence of the highest plant-forms, and which would have been 

 strong opponents in the struggle for existence ; (2) their propaga- 

 tion by spores, being thereby widely disseminated. Nevertheless, 

 there are important differences in the plant-remains of distinct coal- 

 fields. Thus the Carboniferous flora of Xorth America contains a 

 large number of species not represented in that of Europe. 



In Chapter YII. the climate and vegetation of the Carboniferous 

 Period are reviewed according to evidences derived by geologists 

 from its plant-remains found in different parts of the world. Those 

 of the European and Xorth-Americau Coal-measures are abundantly 

 noticed in the foregoing chapters, as they take their places under 

 the different structural or other relationships ; and now (pp. 102, 

 ifec.) that the probable existence of different climatic zones or 

 botanical provinces in the Coal-period has to be discussed, the Car- 

 boniferous (or Permo-Carboniferous) strata and plants of India, 

 South- Africa, and Australia are taken in order. 1. The Lower 

 Gondwana System in India, including the Panchet, Damuda, and 

 the Talchir series. 2. The Karoo formation in South Africa, or 

 rather the Ecca Beds lying just below it. 3. The Wianamatta, 

 Hawkesbury, Xewcastle, and Muree beds of Xew-South- Wales. 

 4. Queensland. 5. Tasmania. These several regions and their 

 formations are tabulated (pp. 122, 123) after Feistmantel and 

 Waagen, to show more particularly the horizons of 1. Glossopteris, 

 2. Glacial phenomena, and 3. Lepidodendron. The essayist is as 

 cautious in giving an o^Mnion in this case as in all the other points 

 of discussion, but seems to accept the opinion expressed by Xeu- 

 mayr, Blanford, and Feistmantel that the Glossopteris flora came in 

 with the cold climate indicated by the glacial conglomerates, and, 

 replacing the older Carboniferous types, spread gradually towards 

 the Xorth, probably from a Southern Continent. 



The recent valuable researches by Clement Reid and others on 

 Pleistocene plants indicative of a cold climate in Britain, as some of 

 Pliocene age witness low mean annual temperatures for Switzer- 

 land and elsewhere at that particular {period, are referred to in 

 Chapter VIII. Further accurate reticarch is required to approach 

 with certainty any conclusion as to climatal conditions in the several 



