Other species with large leaves are Arau caria Bidwilli, the Bunya Bunya of Queensland, and A. Hunsteinii of Kaiser Wilhelm's Land. The remainder of the Australo-Malayan species are small and narrow-leafed, but lofty forms. They centre in New Caledonia with A. Cooki, A. Balansa., A. montana, A. Muelleri and A. Rulei. The two latter have staminate cones of unusual length (24 to 25 centimetres). The majestic Araucaria excelsa, or Norfolk Island pine, was discovered by Captain Cook, who says that on nearing Norfolk Island the stems were taken for basaltic columns! This species attains a height of over 200 feet. The cone scales are winged with a hooked apex. The half-hardy young plants are widely grown in conservatories. Araucaria Cunninghamii, the Moreton Bay pine, is the most widely spread of the Australian species, extending to Cape York and New Guinea.
The genus Dammara (darn'-i-ra.) is con tinental only in Queensland (D. robusta, D. Palmerstoni) and the Malay Peninsula (D. loranthifolia). It is essentially a Malaysian island type. D. obtusa occurs in New Heb rides, D. Moorei is New Caledonian and D. Vitiensis Fijian. D. macrophylla, with the largest leaves of all (17 centimetres long by five broad), is a native of the Queen Charlotte Islands. One of the best-known species is the Amboyna pitch pine, D. orientalis, found also in Java, Sumatra, Borneo and other eastern islands. The highly aromatic gum of this tree, called by Amboyna islanders °Darnmar puti,)) gives its name to the genus. The Kauri pine (or Kowrie), Dammara australis of New Zea land, abundant in the North Island between the North Cape and lat. 38° S., is perhaps the most striking species. The finest forest tree of New Zealand, it often reaches a height of 30 metres and thickness of three metres. But columnar forms with bushy heads may reach 50 metres high by five to seven metres in diameter. Darwin says ('Voyage of the Beatfle'), crown of branches at the sum mit is out of all proportion small to the trunk; and the leaves are likewise small compared with the branches?) The bark is thick and resini ferous. As in the other Dammaran forms the leaves are narrow-based with a broad lamina and much like those of cycads; they are four to five centimetres long by one centimetre broad, thick, leathery and persistive. The seed cones are spherical and five to eight centimetres in diameter, or much smaller than in Araucaria. The rich brown amber yellow Kauri gum or resin is abundant in the sites strength, durability and easy working; lumber ing and destructive fires are fast limiting the forests.
Fossil The geological history of the Araucariales is long. Owing to the re semblance of the wood to that of Cordaitaleans of previous forests in lumps reaching the size of the largest Araucarian cones. The properties are similar to that of the °cat's eye' or Dammar of D. orientalis. This gum oozes from the tree in large quantities in a soft, viscous state. The timber is notable for it is difficult to prove which of the so-called Araucarioxylon types, so abundant in the PaIxozoic, are directly related to the modern forms; hut from the Rhaetic on, the presence of Araucariales closely related to those of to day is well attested. Hollick and Jeffrey de scribe various forms from the Cretaceous of Staten and Long Island. A fine cone called Araucaria hespera occurs with the horned dinosaurs of the Laramie, also a branch (A. Hatcheri) closely related to the Brazil pine. Araucarian types had a wide distribution in the climax forests of both the northern and southern hemispheres during all of the Jurassic, and appear to culminate in the Cretaceous. Toward the close of the Cretaceous they ceased to play a greater role as forest dominants and began a retreat or restriction which lasted throughout Tertiary time, and ended in the scant distribution outlined above. Geologically speaking the Araucariales are very slowly moving toward extinction.
The origin of the Arau cariales, and their relationships to other gym nospermous groups, are uncertain. Neither
systematists nor morphologists are here in ac cord. Every possible hypothesis of descent has been suggested. It is urged (1) that the Arau cariales sprang from Cycadofilicaleans direct, (2) that they are of Cordaitean origin, (3) that they are Lycopodiaceous derivatives, (4) that the Abietinew are the oldest conifers and Araucarians a modern offshoot from them. (I) The possibility of Cycadofilicalean origin is much strengthened by recent investigations of the Cycadeoids. It is now seen that Arau caria has much in common with both Cycads and Cycadeoids: the robust armored stem is analogous to that of the Cycadcoids, this being true of structure, cortical development and both the major and minor branching; the roots freely send up young plants, and seed lings are stout and tenacious of life; the re newed growth of the reproductive shoot from a lateral bud is cycadaceous and cycadeoid; the large pith and thin, woody cylinder of the shoots, vegetative and reproductive, and the complete transition from foliage to fertile scales of the large cones are also cycad-like; while the megasporophyll with its small ligule finds a counterpart in the decurved micro sporophyll of the Cycadeoids. Finally the presence of a leaf gap opposite the outgo ing foliar trace, not only in the cone, but in stem and seedling, is also a Pteropsid feature and not lycopodiaceous. (II) Relationship to the Cordaitales is found in the retention of pitting of the tracheids in different regions of the plant recognized as primitive. Especi ally in the cone the pitting may be as much as five-seriate, with the pits alternate, hex agonal and extending from end to end of the tracheid. As in Cordaiteans, too, the medul lary ray cells are thin-walled and less specialized than in the pines. The resin tissue of the sec ondary wood consists simply in resinous tracheids associated with the medullary rays, and of parenchymd derived from tracheary tissue. Stem and leaf morphology, as well as habitus, suggest Cordaitean affinity. (III) In defense of a lycopodiaceous derivation it is pointed out that Cheirostrobus serves to bridge the gap between the male sporophylls of Arau carp and the Lycopods; that Lepidocarpon, which is outwardly a seed, is the link between the Araucarian seed and the Lycopod sporan gium; that lycopodiaceous wood with its scalari form pitting does not fundamentally differ from Araucanian wood; that transitions be tween the pitted and scalariform sculpturing of the radial tracheidal wall occur in various plants recent and extinct. (IV) The theory of an Abietinean ancestry depends on certain traumatic and on the Cretaceous occurrence of Abietineans (Prepinus) with leaf bundles possessing centripetal wood like those of Cordaites. Even more than the pre ceding views of relationship and descent, this latter theory requires rigid examination in the light of the fossil record and all the evidence it may be made to yield. It has been suggested that all the forms discussed have been dis crete since Palaeozoic time.
Complete references to the literature bearing on the Araucariales will be found appended to the following five major contributions: (Plant Succession,' an analysis of the development of vegetation, by Frederic E. Clements (Carnegie Institution of Washing ton Pub. No. 242, 1916) ; (Cretaceous Conifer ous Remains from Kreischerville, N. Y.,' by Arthur Hollick and E. C. Jeffrey, Mem. New York Bot. Garden (Vol. III, 1909) ; The Araucariex, Recent and Extinct,' by A. C. Seward and Sibille 0. Ford (Phil. Trans. Roy. Soc. London, Series B., Vol. 198, 1906) ; On the Comparative Anatomy and Affinities of the Araucarinez,> by Robert Boyd Thomson (Phil. Trans. Roy. Soc. London, Series B, Vol. 204, 1912) ; Fossil Cycads,) by G. R. Wieland (Carnegie Institution of Washington Pub. No. 34, Vol. I, 1906; Vol. II, 1916).