SPORE-PRODUCING MEMBERS 381 
It remains now to consider the morphological character of the sporangio- 
phore in the Equisetales. The current view of the strobilus of Eguisedum 
is that it is a product of meta- 
morphosis of the sterile shoot, 
and that the sporangiophore 
is an altered sterile leaf. This 
has been re-stated lately by 
Goebel,' on the basis of de- 
velopment of the individual, 
but without bringing the fossil 
Calamarian strobili into. the 
comparison. It may, however, 
be safely asserted that if Lgu/se- 
tum and Lyutsetites had never 
existed, a comparison of the 
Calamarian strobili with those 
of other Pteridophytes would 
have led to a different view; 
it will be necessary therefore 
to examine this natural group 
of the Equisetales as a whole, 
and not only one isolated genus, 
even though that type be the 
well-known one now living. 
Equisetum limosum, L. Median longitudinal section of a 
sporangium at the base of the strobilus, together with the 
annulus (a). 200. 
Taking first the developmental evidence derived from Lgudsetum, as 
me 
Chott 
Aw, 
ait 
Calamostachys Casheana. Tangential section, showing four sporangia grouped around 
their sporangiophore (sf). Three contain megasporesand one microspores. 30. PAdd. 
Trans. W. and S. Well. Coll., 1587. 
(From Scott, Studies in Fossil Botany.) 
given by Goebel,? it is found that, notwithstanding the difference in mature 
form (which Goebel notes, and from which he concludes that the distinction 
1 Organograghy, vol. ii., pp. 499-503. 21.6.5. Px 500. 
