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EXPLANATION OF PLATE XXVI. 
Illustrating Mr. Seward’s paper on Lepidodendron aculeatum. 
Fig. 1. Portion of the petrified specimen showing the leaf-cushions. (Nat. size.) 
Fig. 2. Leaf-trace as seen in transverse section, cut from the specimen shown in Fig. 1, in the 
outer cortex. 
a = junction between parichnos and cortex. 
jt = xylem. 
s = secretory strand. 
b — cambiform cells. 
Fig. 3. Leaf-trace in longitudinal section. 
c= middle cortex of stem. 
p = peridesm. 
/ = secretory tissue. 
x *= xylem. 
Fig. 4. Leaf-trace as seen in transverse section of the stem (Fig. 1) in the middle cortical 
region. Lettering as in Fig. 2. 
Fig. 5. Transverse section of the stem represented in Fig. 1, cut through the scar s shown in 
Text-fig. 1, B. 
Fig. 6. Portion of leaf-cushion converted into coal as seen at the edge of a transverse section. 
