LEPIDODENDRON. 



47 



given at p. 12), by Mr. James Whitaker, of Watersheddiiig Bar, near Oldliam, who has 

 kindly allowed me to shoe the specimen and examine it. 



Figure 2 is a transverse section of the specimen, of the natural size, showing the central 

 axis and sixteen irregularly pear-shaped sporangia, each about half an inch in length, 

 radiating from it. 



Figure 3 represents a longitudinal section (natural size) of the central axis and the 

 scales or bracts, which have a spiral arrangement and support sporangia, ou each side 

 of it. 



Figure 4 is the transverse section of the cone, magnified two diameters, showing its 

 internal structure. The centre, originally composed of cellular tissue, and for the most 

 part destroyed, has been replaced with carbonate of lime. It is surrounded by a zone of 

 hexagonal tubes, having their sides barred by transverse striae. This is bounded on the 

 outside by a sinuous dark line, from which are seen to spring the bundles of l)arred vessels 

 that communicate with the scales or bracts. These vessels traverse, in a highly inclined 

 curve upwards, a band of cellular tissue which has been mostly removed and replaced by 

 mineral matter. The outside of the axis shows elongated cells or utricles arranged in 

 radiating series, similar to what are usually found on the outside of stems of 

 Lepidodendron Harcourtii, and described at length by Messrs. Withani, Lindley and Hutton, 

 and Adolphe Brongniart. 



Fig. 5 is a transverse section of the same part of the axis last described, magnified 

 forty -five diameters. 



Fig. 7 is a horizontal section of a single sporangium (magnified five diameters), showing 

 its irregular pear-shaped form. The wall is composed of one line of transversely elongated 

 cells ; and the inside is a mass of microspores, many of which divide into three, some into 

 four, and others into five sporules, all composed of a yellowish-brown hydrocarbon, 

 resembling crude paraffine in appearance. In every respect this sporangium and its contents 

 sa closely resemble that of the cone described by the late Dr. Robert Brown that a 

 description of one would nearly do for the other. 



Fig. 8 is a vertical section (magnified four and a quarter diameters) of the pedicel and 

 apex of a scale or bract, and of its underlying sporangium, that has an elongated oval 

 form. The scale or bract is chiefly formed of cellular tissue, enclosing in its centre a 

 bundle of vascular tissue, which is seen in the specimen to proceed from the axis and 

 traverse the scale to its apex. The apex is broad, dilated at right angles to the pedicel, 

 produced upwards into a triangular acute point, and downwards into a blunt lobe, as 

 described by Dr. Hooker.^ This sporangium was probably of an elongated oval form, and 

 the notch shown in the lower part of this sporangium towards the axis is due to some 

 disturbing cause, as it is not seen in the other sporangia of the cone. 



Fig. 9 is a longitudinal section of the central axis of the cone, magnified forty-five 

 diameters, showing the place of the pith (most probably composed of cellular tissue, but 



1 ' Mem. Geol. Surv.,' vol. ii, part 2, p. 450. 



