Recmt and Fossil Coniferti. 145 



is another reason for attending to the circumstance, namely, 

 the bold assertion in Mr Witham's Treatise on the Structure 

 of Fossil Trees, that in the vessels of the recent Coniferae, 

 the discs or areolae, as they are called, occur in smgle rows 

 only. 



I have stated that in the Taxodium disticha, there are double 

 as well as single rows of discs similar to those occurring in Pinus 

 strobus and P. canadensis ; and 'this is strictly true with regard 

 to one portion only of the piece of wood I examined. The 

 other portion of the wood presents appearances so totally dif- 

 ferent, that no one could suppose it possible that both existed 

 in the same piece of timber. Whether the peculiarity be a 

 general or only a casual circumstance I am unable to deter- 

 mine, having hitherto had no opportunity of examining any 

 other piece of the same kind of wood. That which I examined 

 grew in the vicinity of London ; its mean diameter is about four 

 inches. The pith is considerably nearer one end of the longest 

 diameter than the other. About two-thirds of the transverse 

 section is of a darkish cream colour. A space about an inch in 

 diameter, with the pith in its centre, is of a chestnut-brown ; the 

 remainder is a shade lighter, or a darkish wood-brown. Now 

 the whole of the pale portion of the wood presents in the longi- 

 tudinal section, parallel to a radius, double and single rows of 

 discs similar to those occurring in Pinus strobus, as shewn in 

 Fig. 2. Plate III. ; but throughout the whole of the darker 

 part, the discs, which occur in single rows only, are so very 

 obscure, that the concentric circles can scarcely be seen. Fewer 

 patches of the discs occur in this than in the paler part ; and 

 £ven where they do occur, the individual discs are always 

 placed at a greater distance from each other. Besides the dis- 

 simihtude of the discs, the longitudinal vessels throughout the 

 dark portion of the wood contain numerous lines or fibres, cross- 

 ing each other nearly at right angles, but inclined to the parti- 

 tions at an angle of about 45^, of which there is not the slightest 

 trace in the pale part of the wood. These lines have often the 

 appearance of a St Andrew's cross, especially when they pass 

 through the discs. As sections both of the pale and dark parts 

 of this singular piece of wood are figured in Plate III., a 



VOL. XVI. NO. XXXI. ^JANUARY 1884. K 



