and suggested area on cone-face. Pollen-grains germinate in the axils of the scales, 

 with haustorial growths: fertilization 13 months after pollination, and seeds matured 

 in 4 more. Adult cone 2-3 in. diam., round and woody, falling to pieces; seeds 

 10 mm., free, with broad unilateral wing: cotyledons 2. Exploited for gum-resin. 



A. robusta (Dundathu Pine), 150 ft., and to 8 ft. diam., most valuable Queens- 

 land timber-tree : leaves 4-6 in. and 1 broad, lanceolate or ovate, spirally arranged, 

 pectinated on laterals. Cones 5 in. by 4 ; seeds with unilateral wing. A fine tree 

 with columnar trunk and spreading branches, gum-resin dries black. 



Dammara orientalis, on mountains of Molucca Is., a large tree, 100 ft. ; leaves 

 2-4 in., and i-| wide, pectinated in 2 series ; dioecious ; cones 4 in. in diam., with 

 distinct effect of ' cone-scale ' on cone-facet. 



Timbers : Araucaria irnbricata, annual rings 5 mm. broad, wood without resin- 

 ducts, all the M. rays uniseriate; pitted tracheides with bordered pits in 1-2 rows, 

 close-set, in patches near ends of tracheides ; when 2-ranked the border assumes an 

 effect of ' hexagonal ' packing. M.R.P. with contracted and attenuated ends, thin 

 walls on all sides, pits flared and bordered, large, 2-7 per tracheide. 



A. excelsa, tropical, with no demarcation of rings ; tracheides with bordered pits 

 close set 1-2 (3) rows. M.R.P. thin walled, contracted ends, with small oblique or 

 flared pits, close set and bordered, 2-9 per tracheide. 



Agathis australis, finest timber, tracheides full of resin ' bars ', rings feebly differen- 

 tiated, 2 mm. Bordered pits in 2 (1-3) rows, close set. M.R.P. 2-6 per tracheide, 

 small, flared and bordered. Pits on tangential walls of summer-wood. 



TAXOIDS: Coniferae are conveniently classed in two main groups as 

 (1) Pinoids, with typically dry 'cones' and wind-dispersed seeds; (2) Taxoids, in 

 which the seeds are solitary, more or less succulent, and dispersed by birds. The case 

 of Juniperus communis shows how a similar biological adaptation may be perfected in 

 the Cupressineae series ; and indications of spiral cone-aggregation may be found 

 in Taxoids (Saxegothea). While the Pinoids (Pinaceae) are taken in four main 

 series, the Taxoids (Taxaceae) are conveniently separated into two, according as the 

 ovules are erect (Taxus) or inverted (Podocarpus). Pollination as before is typically 

 by a drop-mechanism (Taxus), but may be superseded (Saxegothea). 



Special interest centres in Podocarpus (60 sp.), as a great race of forest-trees 

 of the Southern Hemisphere (Australia and New Zealand), very imperfectly known ; 

 strays extending to Pacific Coast, tropical mountains, Africa, E. Indies, China, and 

 Japan : the genus practically corresponds in the S. Hemisphere to Pinus of the 

 North Temperate forest-zone, and presents the case of the type of Conifer most 

 widely divergent from Pi?ms in many respects. Usually dioecious ; timber correspond- 

 ing with that of Taxus ; pitted tracheides with tertiary spiral thickening : foliage- 

 leaves spiral on erect shoots, D.V. and pectinated on laterals {P. japonic a), with one 

 median V.B., and one median duct. Staminate flower of small stamens, spirally 

 arranged, each with 2 pollen-sacs; dehiscence longitudinal, and pollen-grains winged 

 in the manner of Pinus. Ovulate flower remarkable, the ovules being borne solitary 

 in the axil of functionless reduced bract-scale, on an elongated inflorescence-system 

 (P. spicata), or reduced to 2-1 (P. Totara), anatropous, with 'two integuments': 

 the inner delimits the micropyle, and becomes a sclerotesta; the outer, succulent, 

 turns red later, and edible more or less to birds, &c. Special case in P. Totara, 

 60 ft., Totara Pine, New Zealand, with dark-red mahogany-like wood ; the inflores- 

 cence-axis below 2-1 ovules becomes succulent, enlarged like cherry with projecting 

 ' stone ', hence generic name. P. e/ongata of S. Africa with habit of Kauri. 



Comparison of Leaves of Taxoids. 



I. Taxus baccata, needle 1-2 in. and 2 mm. wide : one central bundle, 

 no ducts, no endodermis, no sclerosed hypoderm : palisade 1-2-3 rows, wanting in 

 shade-leaves : guard-cells lignified, in stomatal tracts on lower surface (6 cut in each) ; 

 subsidiary-cells with papillose knobs ; transfusion-tracheides as wing-extensions, with 

 reticulated thickening and pits. 



II. Podocarpus japonica, leaf 2\ in. and 4 mm. wide ; D.V. generalized 

 type ; upper epidermis aqueous, with thick outer wall ; palisade 2-3 rows deep ; one 

 central V.B., and one associated duct on lower surface. Transfusion-tracheides as 

 prominent wing-extensions, with reticulated thickening : stomatal tracts on lower 

 surface, about 15 stomata cut in each. 



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