Weiss. — A Mycorhiza from the Lower Coal-Measures . 265 
EXPLANATION OF PLATES XVIII AND XIX. 
Illustrating Professor Weiss’s paper on a Mycorhiza from the Coal-Measures. 
(Photographs by Mr. Abraham Flatters, Manchester.) 
PLATE XVIII. 
Fig. 1. Transverse section of a mycorhiza from the Cash Collection in the Manchester Museum 
(Q. 827), about 1 mm. diameter. Above the section are seen some dark oval masses, probably the 
excrements of a wood-eating animal. In the exo-cortex (ex) traces of the fungal hyphae can be seen 
projecting from the cell-walls into the cell-spaces. In the medio-cortex (me) are seen dark masses 
(clumps) consisting largely of fungal remains. 
Fig. 2. Vascular cylinder of another mycorhiza 2 mm. diameter from the same slide as Fig. 1 
(Q. 827), showing a well-marked endo-cortex (en). Between the two groups of wood-elements are 
a few parenchymatous cells containing numerous granules, ps = phloem-sheath. 
Fig. 3. Longitudinal section of a mycorhiza from Dr. Scott’s preparation (No. 1527), showing 
the vascular cylinder, the endo-cortex (en), the radially-elongated medio-cortex ( m.c ) with dark 
mycelial clumps, the exo-cortex (ex) with scattered hyphae. 
Fig. 4. Portion of the medio-cortex from a tangential longitudinal section on Dr. Scott’s slide 
(No. 1527), showing the dark mycelial clumps (cl). An enlarged drawing of a portion of this 
photograph is shown in Fig. 4, Plate II. 
PLATE XIX. 
Fig. 1. A portion of the external tissues of the root figured in Plate I (Cash Collection, No. 527), 
showing the fungal hyphae (h) in the exo-cortex and one of the cells of the medio-cortex with clump 
formation (c). 
Fig. 2. A portion of the epidermis from a transverse section of another root, from the same slide 
as Fig. 1, showing the radial course of the fungal hyphae (h) in an epidermal cell. r. h— root-hair. 
Fig. 3. Formation of vesicles by the fungal hyphae in the sub-epidermal layer. Portion of the 
longitudinal section from Dr. Scott’s collection shown in Plate XVIII, Fig. 3. 
Fig. 4. Enlarged view of a portion of medio-cortex shown in photograph 4 on Plate XVIII, 
to show the hyphae connecting the mycelial clumps with the cell-walls. 
Fig. 5. Portion of the cortex of transverse section on Slide No. 1527 (Dr. Scott’s Collection), 
showing one of the large vesicles found near the medio-cortex, and also a cell containing curious 
granulations (see p. 262). 
Fig. 6. Portion of the tangential section on Dr. Scott’s preparation (No. 1527), showing 
sporangia (?) (sp) and spores (?) in a cell of the medio-cortex. The other cells contain mycelial 
clumps (cl). 
Fig. 7. A cortical cell from a transverse section on Slide 529 of the Cash Collection, in which 
the cell-contents seem to have undergone degeneration. 
Fig. 8. Two cortical cells from the same section as Fig. 7, showing earlier stages of degeneration 
of cell-contents with indication of previous formation of mycelial clumps. 
