﻿130 BOTANICAL GAZETTE 



firmly attached t 

 mental plectench 

 connected with margins of gills; X65. 



Fig. 51.— Tangential section of another basidiocarp; gills beginning their 



Figs. 52-55. — Serial tangential sections of a young basidiocarp, from near 

 margin of pileus toward stem; weak general annular gill cavity; shredded 



margin of pileus, shows young hymenophore palisade above cavity forming 

 an even layer; in fig. 53 weak salients are fundaments of lamellae; these more 

 pronounced in fig. 54; in figs. 53 and 54 note palisade layer continuous over 

 margins of gill salients; a few scattered hyphae of fundamental plectenchyma 

 extend across to salients and also to palisade layer between; in fig. 55 gill 

 salients more pronounced and at this young stage marginal palisade cells 

 swelling to form cystidia; in figs. 53-55 note lighter color of trama tissue where 



Fig. 56-63. — Tangential sections parallel with axis of stem and perpendicu- 

 lar to pileus and lamellae, showing independent origin of a secondary lamellae 

 (figs. 56-61) rising between two primary lamellae at left; cells on margins of 

 secondary lamellae also swell into cystidia; in all figures cystidia on margins 

 of gills as well as for some distance back; note elongation of cells in trama of 

 lamellae and subadjacent tissue of pileus with decrease in absorption of stain, 

 due to the growth by elongation which pushes gill fundaments down from even 

 palisade layer of young hymenophore; cells of gill margins interlock with 

 frazzled fundamental plectenchyma on surface of stem; X400. 



Figs. 64-67. — Further stages in attachment of gills to stem. 



Fig. 65. — Rounded edges of gills crowding into thin zone of loose funda- 

 mental plectenchyma on surface of stem; cells interlocking and interwedging; 

 X230. 



Figs. 64, 66, 67.— Transverse section of nearly mature basidiocarp; fig. 64, 

 arrangement of gills and their complete attachment to surface of stems; lysige- 

 nous cavities in stem; depressions ("striae ") above primary gills; X30; figs. 66 

 and 67, details of union of gill margins and stem surface; X 230. 



Figs. 68-71.— Organization of palisade layer on surface of pileus. 



Fig. 68.— Surface of young pileus marked by irregular threads projecting 

 a short distance in large-celled zone of blematogen. 



Fig. 69. — Slightly older stage, showing more compact arrangement of 

 surface elements of pileus. 



Fig. 70.— Still older stage, showing distinct but rather irregular palisade 

 zone forming surface of pileus next blematogen zone. 



Fig. 71. — Nearly mature plant (same as fig. 64), showing details of pileus 

 structure in transverse section; very distinct and well organized palisade 

 layer of surface; note indentations (cross-section of "striae"); blematogen 

 entirely shed by desquamation. 



