147 
The Lindsaya-Type. 
as a fairly bulky strand surrounded by an endodermis into the 
internal phloem of the stele (Fig. 45 B). It is persistent through 
most of the internode but gradually dwindles and disappears before 
the next node below is reached. A transverse section just above 
the node therefore shows the pure Lindsay a- type (Fig. 45 C). 
In Lindsayopsis aculeata (Fig. 46) the internal sclerenchyma 
reaches the next node and joins the incoming strand belonging to 
that leaf-trace, so that a regular solenostele is formed. This differs 
however from a perfectly typical solenostele, owing to the fact that 
the xylem on the ventral side of the internal phloem is considerably 
thicker than the dorsal arch of xylem ; though this difference is not 
so extreme as in certain species of Lindsay a and Odontoloma. 
Finally in two species of Lindsay a , L. cidtrata and L. retusa, a 
i 
typical solenostele is present. 
