SECTIONAL TRANSACTIONS.— K. 497 



(Hamamelidaceae) now exclusively Asiatic, but also by certain fossil pollen 

 forms belonging to widely distributed genera such as Alnus, Corylus and 

 Acer, which are most nearly related to the Asiatic species of these genera. 

 Similarly leaf-impressions referred to Vitis, Celtis and Quercus can be most 

 closely matched with the leaves of living Far Eastern forms. Reference is 

 also made to the climatic implications of the flora and its relations to other 

 early Tertiary floras in Europe, North America, the Arctic regions, and the 

 Far East. 



Dr. R. Florin. — The morphology of the female cone in palceozoic conifers 

 (10.45). 



The old and important problem of the morphology of the female cone in 

 the Conifers may profitably be considered in the light of the oldest known 

 remains. 



Instead of ovuliferous scales the cones of Walchia piniformis had radially 

 built short shoots bearing spirally arranged scale-like appendages and 

 placed in the axils of bifurcated bract scales. One of the appendages on 

 the inner side of the short shoot bore one single erect and somewhat flattened 

 ovule in a terminal position. The ovules had two archegonia and a single 

 integument, which probably originated from a division of the scale-like 

 appendage just below the ovule. 



In other species of the same group (Stephanian — Lower Permian) the 

 fertile short shoots were more or less flattened, and showed various stages 

 of transition towards the ovuliferous scales of Ernestiodendron (Lower 

 Permian), Pseudovoltzia (Upper Permian), and Voltzia (Triassic). 



The female cone of Walchia piniformis was built essentially on the same 

 plan as that of Cordaites. In this genus, however, a still more primitive 

 structure has now been found, characterised by the short shoots having 

 fertile appendages with a repeatedly divided apex, and one or two seeds each. 



The structure of the female cones in Cordaites and in the conifers is most 

 readily interpreted in the light of the telome theory. 



Dr. H. S. HoLDEN. — The structure of the rachis in Rachiopteris cylindrica 

 ("•IS). 



Prof. W. T. Gordon. — On Tetrastichia bupatides, a primitive Pteridosperm 

 of Lower Carboniferous Age (11.45). 



Theoretical considerations indicated that surfaces of minor unconformity 

 in bedded volcanic ashes might prove useful levels along which to search 

 for examples of the flora, and perhaps the fauna, coeval with the periods of 

 eruption of the volcano. Plant remains in particular might be expected to 

 occur occasionally in a petrified state. In rocks of Lower Carboniferous age 

 at Oxroad Bay, North Berwick, the theory was borne out, and, among the 

 plants, a new pteridosperm, to which the name Tetrastichia bupatides has 

 been given, was fairly common. 



The internal structure of this form is simpler than in any other of its 

 class. The stele of the axis is cruciform in section, and entirely composed 

 of xylem elements. The inner cortex contains sclerotic nests, and the outer 

 cortex many secretory cells and a marked hypodermal meshwork of groups 

 of elongated fibrous elements. The mesh is long and narrow, but becomes 

 dilated when secondary thickening of the stem takes place. A smooth 

 epidermis, containing stomata in which the guard-cells are flush with the 

 surface, encloses the other tissues. 



