66 DESCRIPTIVE CATALOGUE 



Family ARAUCARINE^E. 



Only two living genera compose this family, Ayatliis and 

 Araucaria, and both are from the Southern Hemisphere ; but 

 numerous fossils of wide-ranging variety must be included 

 in it. 



The salient feature of the living forms is the presence of only 

 one seed on the seed-scale, which appears to be a single scale, 

 and if it is compound in its origin, it is, at any rate, completely 

 fused to form one structure now. Both male and female sporo- 

 phylls form large cones, spirally arranged. The leaves arc 

 simple, generally broad-based, often large ; though small, ad- 

 pressed foliage is present in some species. The wood is without 

 resin-canals, the pitting on the radial walls of the medullary 

 ray-cells is bordered, and there are- generally several pits per 

 tracheid-field. The pits of the secondary tracheids are often 

 adjacent and hexagonal!}' compressed, in alternating rows, though 

 in some parts of even an old tree this feature may be absent. 



The family is well described by Scward & Ford (1906). It 

 plays an extremely important part in the palaeontologists' 

 records. Its type of secondary wood is almost universal in the 

 Palaeozoic, and was widespread and common in the Meso/oir 

 and Tertiary, in which deposits the- remains arc supplemented 

 by cone-scales, foliage-branches, etc., showing undoubted Arau- 

 carian affinity. 



Though now restricted to the Southern Hemisphere, the 

 family was widely spread in Europe and Xorth America as well 

 as Asia so late as the mid-Tertiary. Good remains of Araiu-aria 

 itself arc found in the British Eocene (see Gardner,. 1886, 

 pi. xii, etc., and others). Members of tire family are also recorded 

 in the Weajden and Jurassic of this country, and there are 

 many European records of Arancarians from various Mesozoic 

 and Tertiary deposits (e.g. Fliche (1896), Velunovsky (1885), 

 and innumerable others ; Cretaceous records will be found 

 listed hi Stopes, 1913), as well as American representatives 

 (seo Berry, 1911, where the Lower Cretaceous, and Knowlton, 

 1898, where also the Tertiary records are listed). It is there- 

 fore a matter of extreme surprise that there are no representa- 

 tives of the Araucarinece in the British Lower Grcensand. It 

 must, of course, be remembered that the material already 



