TEMPSKYA. lB 7/ 
If we turn to the histological structure of Zempskya we find, as 
a rule, the mineralization of the tissues has been very partial, as 
indeed the extremely porous texture of most of the specimens 
sufficiently indicates. Schenk’s figure affords a good example of 
this incomplete preservation. In some specimens in the Botanical 
Department of the British Museum, to which Mr. Carruthers was 
kind enough to draw my attention, the structure is unusually well 
shown. Unfortunately in the case of some of these slides there 
seems to be some doubt as to the exact locality from which the 
specimens were obtained. I am also indebted to Mr. Boodle of 
the Royal College of Science for the opportunity of examining 
some very interesting sections of Zempskya in his possession, of 
which he hopes shortly to publish a full description. 
The chief feature in specimens of Zempskya in which the details 
are more perfectly preserved is the large number of root sections 
of various sizes; the central vascular bundle is occasionally 
exceedingly distinct, and shows a diare xylem group, of which 
the larger tracheids have a scalariform or reticulate pitting. 
Immediately surrounding the tracheids there is a space left by 
the disorganization of the phloem; and, external to this, several 
layers of thick-walled elements, followed at the periphery of the 
root by a thin band of parenchyma which, in some cases, shows 
a remarkably distinct piliferous layer with long and narrow root 
hairs. These sections in which the root hairs have been preserved 
appear to be identical with those figured by Corda in Protopteris 
Cottai.1 Transverse sections of the roots of Dicksonia antarctica 
agree very closely with these fossil roots; we have the same type 
again in Protopteris microrhiza and P. confluens, Stenz., as figured 
by Stenzel.’ 
In addition to these smaller diare root bundles, some of the 
British Museum slides of Zempskya show larger groups of tracheids 
of a more or less triangular form which may be sections of larger 
root axes. There is distinct evidence in the great variation in size 
of the root sections that we are dealing with a mass of branched 
root structures. 
Associated here and there with these adventitious roots, some 
of the examples of Zempskya occasionally show sections of larger 
1 Flor. Vorwelt, pl. 1, figs. 1-5. 
* Nova Acta Ac. Cs, Leop.-Car. vol. xxvi. 1858, pls. xviii. and xix. 
