66 UEOLOGY OF LOWER ME80Z0IC ROCKS OF QUEENSLAND, 



Cycads may ultimately be very greatly increased, if it should be 

 shown that the genus Tce/)iiopteris belongs to this group. In a 

 recent publication, Thomas includes species of Tceniopteris with 

 the Cycadophyta, as a result of his examination of the epidermis 

 of a number of recent and fossil Cycads.* None of the Queens- 

 land Lower Mesozoic examples of Tceniopteris obtained have 

 been preserved as carbonaceous films, and it is at present impos- 

 sible to state the nature of the structure of the epidermis in 

 them. 



The list of species in this Series may be summarised, and the 

 figures expressed in percentages, as in the following Table : — 



Such tables as these must be used with a good deal of caution, 

 as their indiscriminate use may lead to quite incorrect and even 

 absurd results; but careful use, with a full realisation of their 

 value and their drawbacks, may yield interesting and, to some 

 extent, reliable results. The use of such numerical methods has 

 not come into very general use, but their preparation and use 

 have been illustrated recently by VV ieland.f 



In the above Table (Table i.) of the Ipswich flora, the species 

 of Stachyopitys, and gymnospermous seeds have not been used, 

 since they, in all probability, represent seeds or reproductive 

 organs of plants already represented in the list by sterile fronds. 

 The species of Tceniopteris are placed separately in the Table, 



* Thomas, Q.J.G.S., Ixix.; p. 223. 

 t Anier. Journ. Sci., xxxvi. (1918), pp.268-278. 



