Barber . — Cupressinoxylon vectense. 349 
that of the pits shows that there is barely room for two 
rows of pits in one cell. We should not therefore meet with 
a double row of pits unless two tracheides were placed exactly 
opposite one another. This arrangement of cells, as already 
mentioned, is more frequently met with in the root-specimens, 
and we accordingly find one or two instances in the root- 
sections of two bordered pits occurring side by side at the 
same level on the wall of one tracheide (Fig. 10). 
In branch (1) and branch (2) the pits are usually quite free 
from one another, very rarely touching or slightly compressed. 
They are however much more abundant at the ends of the 
tracheides. In root (1) the pits, while generally free, are 
often in close contact, especially at the cell endings, the 
result being that their shape is oval with flattened upper 
and lower sides. The pits are sometimes flattened in root 
(2), but the structure is not well enough preserved to institute 
comparisons. 
Bordered pits in Coniferae usually show two concentric 
circles in surface view, the outer and inner borders. It has 
been customary to determine the width of these circles most 
accurately in the hope of thus obtaining data for the separa- 
tion of different plants. From the extended researches of 
Kraus 1 , Wille 2 and others, it does not seem that there has 
been much progress made in this direction. 
In the present specimens much difficulty has been experi- 
enced because of the varying state of preservation. At first 
this caused a good deal of unnecessary labour. It was found 
that in parts of some sections the pits showed more than 
two concentric circles (Fig. 15) ; in other cases the two circles 
could hardly represent the outer and inner borders of the 
pit, because of the large and varying size of the inner one. 
The appearances referred to evidently point to different 
stages of decomposition, some of them closely resembling 
for instance those figured by Hartig in his description of 
1 Kraus, Beitrage zur Kenntniss. fossil. Holzer, II, Zur Diagnostik des Coni- 
ferenholzes, Abhandl. d. naturf. Ges. zu Halle, xvi, 1886. 
2 Wille, Zur Diagn. d. Coniferenholzer, lialle, 1887. 
