530 
W. H. SAWYER, JR. 
DESCRIPTION OF PLATES XXVIII-XXIX 
The following microphotographs were made by the author, some with the Spen- 
cer Lens Co.'s horizontal camera with Zeiss lenses, the others with a Bausch and 
Lomb microscope equipped with Zeiss lenses and a Bausch and Lomb vertical camera 
attachment. 
Plate XXVIII 
Fig. I. Primordium of the basidiocarp. The hyphae are closely interwoven 
to form a compact structure. Many interhyphal spaces occur, scattered through the 
fruit-body. On the outside are a few blematogen hyphae. X50. 
Fig, 2. A fruit-body somewhat older than the preceding. The stem fundament 
is differentiated to near the apex, where the hyphae are still in the loose primordial 
condition. On the sides may be seen the basal parts of blematogen hyphae, their 
outer ends having been lost. X30. 
Fig. 3. An enlargement of the right side of the preceding figure. The loose 
blematogen threads are shown growing out from the compact stem cortex, X215. 
Fig. 4. A young fruit-body after formation of the stem primordium. The 
blematogen may be seen enveloping the stem fundament. X30. 
Fig. 5. A slightly older stage, showing the blematogen radiating from the stem 
cortex. The latter is compact; the apex is slightly more deeply staining, showing 
that growth is more active at that point. X30. 
Fig. 6. A state slightly older than the one shown in fig. 5. By interstitial 
growth the stem apex has become bulbous, forming the pileus primordium. Outside 
is the blematogen. X50. 
Fig. 7. A fruit-body in median longitudinal section that is a very little older 
than the one shown in Fig. 6. The pileus fundament is a little larger and the hyphae 
in the peripheral zone are growing straight outward over its entire surface. X50. 
Fig. 8. Median longitudinal section. By epinastic growth the outer, lateral 
hyphae have grown downward to form the pileus margin, which appears as a small, 
deeper stained area on either side. X30. 
Fig. 9. An enlargement of the right side of Fig. 8. Near the center can be 
seen the pileus margin, whose hyphae extend in a downward and slightly outward 
direction. Immediately below it the ground tissue is beginning to break away to 
form the gill cavity. On the outside, at the right, is the loose universal veil. X 115. 
Fig, 10. An older stage; the hymenophore primordium appears on either side, 
on the margin of the pileus. Over the pileus the brown, enlarged hyphae of the 
blematogen stand straight outward. X30. 
Fig. ii. An enlargement of the right side of Fig. 10, showing details of above 
mentioned structures and early indication of formation of the gill cavity. X115. 
Fig. 12. Tangential section, showing the uneven condition of the hymenophore. 
Below the ragged surface of the latter the ground tissue is beginning to break away 
to form the gill cavity. X50. 
Fig. 13. Tangential section of the same fruit-body, but nearer to the stem. 
The hymenophore is becoming more even and the gill cavity is much better formed. 
X50. 
Fig. 14. Median longitudinal section. On the left may be seen the duplex 
nature of the blematogen over the pileus margin. X30. 
