99 THE “BLUING’’ AND THE” “BED ROD) JOH DEED PLNE 
becomes equally rapid. The blue color appears around the beetle 
holes soon after the entrance of the ‘“‘ blue” fungus. Usually it forms 
two rings extending from the hole along the wood fibers. Various 
stages of this first appearance of the color are shown on Pl. IX. The 
spread of the ‘‘ blue” fungus within the wood, through the agency of 
wood-boring beetles, is an occurrence frequently found in many conif- 
erous woods. The central figure at the bottom of Pl. IX is froma 
photograph of a log of western hemlock found in the Olympic Forest 
Reserve, in Washington, which shows an even more striking case of 
the spread of Ceratostomella from holes made by Gnathotricus occi- 
dentalis Hopkins MS. This particular piece of wood was cut from 
a fallen trunk, about 6 inches in from the bark. 
FRUITING ORGANS OF THE ‘*‘BLUE”’ FUNGUS. 
The ‘“‘blue” fungus forms its fruiting bodies on the surface of the 
wood in which it is growing. Air seems to be necessary for the for- 
mation of the fruiting bodies. A good deal of moisture in the sur- 
rounding air is necessary likewise. No fruiting organs are formed in 
dry air. In the forest they occur in the cracks formed when a blued 
trunk is broken off, on broken branches, and at such other points as 
are exposed to the air. So far the writer has been unable to find the 
perithecia of Ceratostomella on the surface of standing trunks under 
the bark, although a diligent search has been made for them at all 
seasons for two years. When, several months after the beetle attack, 
the bark becomes loose, so that it separates from the wood, a space 
is left between the bark and wood. In this space numerous fungi 
develop in quantities, among others a species of Alternaria which lines 
the pupal chambers of the Dendroctonus, and a species of Verticillium. 
The whole atmosphere of this region is surcharged with moisture, and 
yet the ‘‘blue” fungus does not fructify here, for there is probably 
not enough air. 
The black perithecia of the ‘‘ blue” fungus, Ceratostomella pilifera 
(Fr.) Winter, are familiar objects on blued boards or shingles, where 
they occur in thousands side by side. The perithecia are formed 
within a few hours when the conditions are favorable. At various 
points on the surface of the wood, in some instances out of every 
medullary ray, masses of hyphe grow out forming a dense mass which 
gradually develops into an egg-shaped body (Pl. VII,4). The surface 
of the young perithecium shows irregular polygonal markings, which 
gradually become indistinct as the perithecium turns jet black almost 
to its tip. At the tip of the young perithecium a number of hyphe 
grow out parallel with one another (Pl. VII, 4) in a direction perpen- 
dicular to the substratum. They remain coloriess at the tip. These 
hyphe grow in length with remarkable rapidity and form a long 
