156 ON THE FOSSIL FLORA OF THE COAL DEPOSITS OF AUSTRALIA, 



two cotyledons. There are probably nearly two hundred species 

 known, dispersed over a great part of the globe, several of them 

 forming large forests in temperate climates, or more rarely within 

 the tropics; while some of them extend almost to the utmost 

 limits of woody vegetation in high latitudes, or at great elevations. 

 They are distributed into about twenty-five genera, forming three 

 tribes or sub-orders: — 1. Abietinese, with the fruits collected in cones 

 and inverted ovules ; of this the principal genera are Pinus 

 (including Abies), Araucaria, Cunninghamia, Sequoia, &c. 2. 

 Cupressineae, with the fruits collected in cones and erect ovules ; 

 including Juniperus, Callifcris, Thuja, Cupressus, Taxodium, Cryp- 

 tomeria, &c. 3. Taxinese, sometimes considered as a distinct 

 family, with the fruits solitary or loosely spiked, including Podo- 

 carpus, Dacrydium, Phyllocladus, Salisburia, Taxus, &c. 



The woody tissue of the trees of this family is seen to be marked 

 with pecular circular dots or punctuations, when examined under 

 the microscope. The ovules at the base of each cone-scale are 

 generally held to be naked, each ovule having a large opening at 

 its apex, to which the pollen from the anthers is applied directly. 

 But some say that the ovules are not naked, but are contained in 

 a proper ovary, which is closely applied to the seed ; that the outer 

 membranous scales are modified leaves ; and that the hard scales 

 are altered bracts bearing the pistillate flowers 



Some botanists look upon Conifers as the highest type of true 

 dicotyledons. 



We have abundant evidence of the existence of Conifers in 

 Australia, in almost all our plant beds except the very earliest coal 

 formations. This is necessary to bear in mind, because Morris in 

 Strzelecki's work already referred to, lays stress upon the absence 

 of such woods from the N .S. Wales specimens. Wood, leaves and 

 scales of Conifers, are mentioned by Dana. Many specimens of 

 coniferous wood, are reported to occur in the lower coal measures, 

 Greta Creek. Wood and leaves are found in the Jerusalem Coal 

 Basin in Tasmania, and both are common as we have seen in 

 the Ipswich coal beds and in the Tivoli Mines in Queensland. 



