Jeffrey . — The Wound Reactions of B r achy phy llum. 385 
a healed wound. The fact that the material was partially carbonized, 
especially in the region of the wound, made it difficult to secure satis- 
factorily thin sections through the traumatic region. This was regrettable 
on account of the fact that the black opacity of the tissues made thin 
sections particularly desirable. However, the partial burning of the material 
has on the whole been an advantage, for it has resulted in a superb con- 
dition of preservation. Photograph 3, Plate XXVII, shows a section through 
the partially callused wound, under a low magnification. Two folds of 
traumatic wood are seen overlapping the injured surface in the manner 
characteristic of ligneous wounds. Photograph 4, Plate XXVII, represents 
a view of a section either on a lower or higher plane than that shown in the 
last photograph. It is of course not possible to decide which alternative is 
the correct one, in view of the fragmentary condition of the piece of wood. 
The wound is closed over in the centre, at this level, as may be seen by 
comparing the two narrow annual rings, most clearly discernable on the left 
of the wound, with the two similar rings in the foregoing photograph. By 
the use of a lens, it may be observed, that stretching away tangentially on 
either side of the wound is a row of apertures in the wood. These are 
traumatic resin-canals. Photograph 5, Plate XXVII, shows the right margin 
of the wound in photograph 4, much more highly magnified. Towards the 
left of this photograph is a mass of resiniferous parenchyma, such as is 
found in connexion with healing wounds in nearly all Conifers. To the 
right of this mass of resinous parenchyma extends a tangential series of resin- 
canals. Photograph 6, Plate XXVII, shows the continuation of this series 
of traumatic canals, beginning about the centre of the former photograph. 
On the left of photograph 6 may be recognized the same canals as are 
found in the centre of photograph 5. These series of canals stretch to the 
extreme margins of the fragment of wood. Photograph 7, Plate XXVII, 
shows a row of canals from a plane of section so far removed from the actual 
wound, that there is scarcely any evidence of traumatic disturbance in the 
arrangement of the elements of the wood. In this photograph it is possible 
to distinguish, that although there are no resinous elements in the wood 
proper, dark coloured cells surround the traumatic resin canals. Photo- 
graph 8, Plate XXVII, shows one of the larger canals highly magnified. 
The contents of the resiniferous cells surrounding the canal are so dark, that 
they present no actinic contrast with the almost black walls of the cells 
themselves. In photographs 7 and 8 it is possible to make out that the 
row of traumatic resin-canals occur in the autumnal wood of the specimen 
under discussion. Photograph 9, Plate XXVII, is of a longitudinal section 
of the same piece of lignite, showing a traumatic canal in longitudinal 
section. The canal is obviously lined by dark hued cells and is constricted 
at intervals. The latter feature is found in the case of traumatic and even 
normal resin-canals in the Abietineae. The canals are jacketed not only by 
