288 Sinnott and Bartlett — Coniferous Woods. 



vicinity of the healed wound the rays are much taller than in 

 normal wood, sometimes ten cells high. 



Relationships. 



This interesting fossil apparently belongs to that ever enlarg- 

 ing group of forms which have been regarded as intermedi- 

 ate between Abietineae and Araucarineae. According to the 

 definitions of both Goeppert and Gothan it would certainly 

 be classed as a Cupressinoxylon, since it possesses both wood 

 parenchyma and thin-walled rays; but those insignificant though 

 taxonomically important structures, the so-called " bars of 

 Sanio," seem to be quite lacking. The absence of these has 

 been cited by Jeffrey, Sinnott, Miss Gerry, Miss Holden and 

 others as an indication of araucarian affinity. Chiefly on this 

 basis (but also from other evidence) a considerable number of 

 genera and species, otherwise resembling Cupressineae, Taxo- 

 dineae or Podocarpineae in their internal or external struc- 

 tures, are now treated as " masquerading " araucarians. So 

 regarded are species of Brachyphyllum, Geinitzia, Widdring- 

 tonites, Raritania, Androvettia and others by Hollick and Jeff- 

 rey (1. c.) ; Araucariopitys by Jeffrey*; Paracedroxylon by 

 Sinnottf and Paracupressinoxylon, Paraphyllocladoxylon, Meta- 

 cedroxylon and Xenoxylon by Miss Holden (1. c). The occur- 

 rence of mutually flattened pits was regarded by Hollick and 

 Jeffrey as the chief evidence of araucarian affinity. Jeffrey 

 has since adopted the absence of " Bars of Sanio " as a much 

 more reliable criterion. To be sure, this criterion must be 

 used with caution in dealing with fossil tissues, since it seems 

 to be easily affected by conditions of preservation. In our 

 charcoal material of Podocavpoxylon JlcGeei, for example, a 

 few rather badly crushed fragments still showed the character 

 of the pitting very well but, save infrequently here and there, 

 no traces of " Bars of Sanio." However, the large number of 

 fossil species already described, many of them beautifully pre- 

 served, which entirely lack "Bars of Sanio," together with the 

 evident similarity among these in such characters as extreme 

 microphylly, shallow medullary rays and, somewhat less often, 

 of flattened pitting and traumatic resin canals, all combine to 

 indicate the existence in the Jurassic and early Cretaceous of a 

 rather large group of conifers intermediate in many characters 

 between Abietineae, Cupressineae and Podocarpineae on the 

 one hand and Araucarineae on the other, but generally inclin- 

 ing toward the latter. 



* Jeffrey, E. 0., Araucariopitys, a new genus of Araucarians, Bot. Gaz., 

 xliv, 435-444, 1907. 



f Sinnott, E. W., Paracedroxylon, a new type of Araucarian wood, Kho- 

 dora, xi, 165-173, 1909. 



