340 Barber . — Cupressinoxylon vectense . 
of growth even in those plants which have rigidly-defined 
rings in their stems and branches h As will be seen directly, 
our specimens probably include both branches and roots. 
I have observed gradual rings in branches of Abies Pinsapo, 
Cryptomeria japonic a, juniper us Virginian a, . and especially 
Juniperus communis , although the rings are well separable 
and easy to follow. The sections of Cupressus sempervirens 
in Nordlinger’s famous series, on the other hand, show a con- 
fused arrangement of gradual and normal rings frequently 
anastomosing with one another, and rendering the counting 
a matter of considerable difficulty. The resemblance between 
these sections and our fossil is very striking. In the other 
cases just mentioned the gradual rings may be regarded as 
exceptionable disturbances in the wood-formation ; in Cu- 
pressus sempervirens the irregularity appears to be the usual 
state of affairs. Thus Hartig describes two branches of this 
Cypress, one fifteen to twenty years old, showing only three 
rings of growth, and one twenty-five years old with nine 
rings 2 . Through the kindness of Mr. Thomas Hanbury 
I have been able to examine the branches and roots of 
two trees of this species from his garden at La Mortola. 
A study of these specimens confirms the previous observa- 
tions. There are the gradual and the sudden rings, the 
anastomosis of the narrow dark bands, and even a tendency 
to the formation of bundles of small rings, usually two 
together, alternating with clear zones, which forms so marked 
a character of our fossil specimens. Such irregularity as 
this cannot be referred to external conditions, and, as we 
have seen, the rings of this Cupressus do not of necessity 
correspond to definite periods of time. I have accordingly 
felt justified in including the irregularity in the formation 
of the annual rings among the distinguishing characters of 
the fossil under discussion. 
We are sometimes able, from a study of the arrangement 
of the tracheides in a transverse section, to tell whether it 
1 Nordlinger, 1 . c. 
2 Hartig, Vollst. Naturgesch. d. forstl. Kulturpflanzen Deutschlands, p. 86. 
