832 REPORT — 1903. 



Eastern Asia; under the shade of their trees lived ' the stupid, salamander-like 

 Labvrinthodonts, -which pottered with much belly and little leg, like Falstatt'in 

 his old age.' The plants of these Palreozoic forests seem to be revivified, as we 

 subject their petritied fragments to microscopical examination, llobert Louis 

 Stevenson has referred to a venerable oak, which has been growing since the 

 Ileformation and is yet a living thing liable to sickness and death, as a speaking 

 lesson in history. How much more impressive is the conception of age suggested 

 by the contemplation of a group of Paheozoic tree-stumps exposed in a Carboni- 

 ierous quarry and rooted whei-e they grew ! An examination of their minute 

 anatomy carries us beyond the mere knowledge of the internal architecture of their 

 stems, leaves, and seeds ; it briugs us into contact with the actual working of their 

 complex machinery. As we look at the stomata on the lamina of a leaf of one 

 of those strange trees, and recognise a type of structure in the mesophy 11- tissues 

 which has been rendered familiar by its occurrence in modern leaves, it requires 

 but little imagination to see the green blade spreading its surface to the light to 

 obtain a supply of solar energy with which to extract carbon from the air. We can 

 almost hear the murmur of plant-life and the sighing- of the branches in the wind 

 as the sap courses through the wood, and the leaves build up material from the 

 products of earth and air ; products that are to be sealed up by subsequent 

 geological changes, till after the lapse of countle.ss ages the stoi-e of energy accu- 

 mulated in coal is dissipated through the agency of man. 



The minute structure of the wood of the Calamites, Ijycopods, and other trees, 

 agrees so closely with that of existing types that we are forced to conclude that 

 these Palajozoic plants had already solved the problem of raising a column of water 

 more than 100 feet in height. The arrangement of the strengthening or mechanical 

 tissues in the long tiat leaves of Conlaites is an exact counterjjart of that which 

 we find in modern leaves of similar form. The method of disposition of support- 

 ing strands in such manner as to secure the maximum eH'ect with the least 

 expenditure of material, was as much an axiom in plant architecture in the days 

 of the coal-forests as it is now one of the recognised rules in the engineers craft. 



We need not pause to discuss the various opinions that have been expressed as 

 to the conditions under which the forests grew ; we may adopt Neumayr's view, 

 and recognise a modern parallel in the moors of the sub-arctic zone, or find a clo.se 

 resemblance in the dismal swamp of North America. There is also the view 

 expressed many years ago hy Binney and warmly advocated by Darwin, that some 

 at least of the Coal-period trees grew in salt-marshes, an opinion which receives 

 support from several structural features suggestive of xerophytic characters 

 recognised in the tissues of Palaeozoic plants. 



Time does not admit of more than the most cursory glance at the leading types 

 of the Permo-Carboniferous floras. The general character of the preceding a ege- 

 tation is retained with numerous additions. Archepocalamites is replaced by a 

 host of representatives of the genus Calmnites, an Equisetaceous type with stout 

 woody .stems and several forms of cones of greater complexity than those of modern 

 Horsetails. Side by side with the Calamites there appear to have existed plants 

 which, from their still closer agreement with F.quisetum, have been described by 

 Zeiller, Kidston, and others as species of Equkctites. The genus Sphenopln/llum, 

 a solitary type of an extinct family, was represented by several forms which, like 

 the Galium of our hedgerows, may have supported their slender branches against the 

 stems of stronger plants. Lycopods, with trunks as thick and tall as forest trees, 

 were among the most vigorous members of the later Palasozoic forests. Although 

 recent research has shown that several of the supposed ferns must be assigned to 

 the Cycad-fern alliance, there can be no doubt that true ferns had reached an 

 advanced state of evolution during the Permo-Carboniferous epoch. The abund- 

 ance cf petritied stems of the genus Psaroniufi, of which the nearest living repre- 

 sentatives are probably to be found among the tropical Marattiacese, demonstrates 

 the existence of true ferns. Others had more slender stems which clambered over 

 the trunks of stouter trees, while some grew in the shade of Lepidodendron and 

 Cordaites. The most striking fact as regards the Permo-C^arboniferous ferns is 

 the abundance of fertile fronds bearing sporangia which exhibit a mors or less 



