iqiq] walker— PLUTEUS AND TUBARIA 19 



EXPLANATION OF PLATES I-V 



The photomicrographs were made by the author as follows: figs. 1-28, 

 51-77 with a horizontal Zeiss camera; figs. 29-50, 78-93 with a Bausch and 

 Lomb vertical camera and Zeiss lenses. Detailed explanations of figures 

 may be found in the text. 



PLATES I-III 



Pluteiis admirahilis 



Fig. I. — Median longitudinal section of young basidiocarp showing differ- 

 entiation into primordia of stipe, pileus, and hymenophore; X31. 



Figs. 2, 3. — Median and tangential longitudinal sections of sHghtly older 

 basidiocarp, with well organized palisade layer; X31. 



Figs. 4-8. — Successive stages in development of pileus; X31. 



Figs. 9-11. — Median and tangential longitudinal sections of slightly older 

 basidiocarp; X3i. 



Figs. 12-14. — Similar sections of depauperate fruit body in which develop- 

 ment had been arrested when gill salients were forming; X31. 



Figs. 15-18. — Median and 3 tangential longitudinal sections through 

 basidiocarp just older than preceding. 



Figs. 19-22. — Position of these sections indicated in text fig. 2; X31. 



Fig. 23. — Median longitudinal section of basidiocarp nearing maturity; 



X3I- 



Fig. 24. — Horizontal section through a basidiocarp about same age as 



shown in figs. 19-22, showing strong attachment of gills to stipe; X31. 



Figs. 25-28. — Successive stages in development of gills; X31. 



Fig. 29. — Higher magnification of fig. i, showing beginning of hymeno- 

 phore; X225. 



Figs. 30, 31. — Higher magnifications of basidiocarp shown in figs. 2 and 3, 

 showing detail of palisade layer ; X 2 2 5 . 



Fig. 32. — ^Detail of a part of fig. 8, showing interweaving of filaments of 

 pileus and stipe, giving appearance of endogenous development; X225. 



Figs. t^T), 34. — Higher magnifications of sections shown in figs. 12 and 13; 

 X225. 



Fig. 35. — Higher magnification of fig. 10; X225. 



Fig. 36. — Detail of section shown in fig. 18; X225. 



Fig. 37.— Detail of part of fig. 22; gill salients appear on incurved part of 

 pileus; X225. 



Fig. 38. — Young gills from basidiocarp shown in fig. 20; X225. 



Fig. 39. — Part of hymenophore as seen on margin of pileus shown in fig. 24; 

 X225. 



Fig. 40. — Portion of surface of basidiocarp shown in fig. 23; X225. 



Fig. 41. — Portion of surface of pileus of basidiocarp nearing maturity, 

 showmg character of surface of mature fruit, and loosening of tissues during 

 expansion. 



