OF EQUISETALES 149 
verticil: these variations in number of the sporangiophores would be 
difficult to harmonise with any reference to “leaf-segments,” as ordinarily 
understood elsewhere; and their disposition suggests the idea of chorisis 
of the sporangiophore similar to that seen frequently in the stamens of 
Angiospermic flowers. 
Forked sporophyll of Sphezo- 
phyllunt majus, bearing  spor- 
angiophore. (After Kidston.) 
us 
Wl 
Calamostachys. Diagram of Equisetum maxtmum, Link. A, the 
cone in radial section, av <i upper part of a fertile axis, with the lower 
which bears successive vert half of the strobilus. Natural size. 6=the 
bracts (47), and peltate sporangio- leaf-sheath. @=annulus. x=stalks of spor- 
phores (sf). s#7z2=sporangia borne angiophores cut off. y= transverse section of 
on the sporangiophores. As the axis, &=sporangiophores in ous posi- 
bracts are alternate one tions, slightly enlarged. st=stalk. se= 
another their upturned tips are sporangia. s=enlarged distal end. (After 
only shown in every alternate - Sachs.) 
verticil. (After Scott.) 
In the Equiseta and Calamarians, spore-bearing bodies of outline not 
unlike those of Psilotaceae are attached directly to the axis itself, and bear 
the pendent sporangia (Fig. 79). They show sometimes almost constant, 
but frequently inconstant, numerical and local relation to the whorls of 
