carpia is usually of the sphenopteroid type and frequently 
investigators, in discussing the genus, fail to consider 
the fact that the foliage may be pecopteroid. 
The chief species of the sphenopteroid series is Ol- 
gocarpia brongniarti Stur® and the best known of the 
pecopteroid series is O. gutbieri Goeppert,‘ although even 
in this species the foliage is more or less sphenopteroid. 
In all of the species in which the sporangia are known, 
there has been observed a more or less transverse annu- 
lus which resembles in great detail that found in the 
genus Gleichenia. There is some evidence indicating that, 
at least in a few species, the sorus is synangial, even 
though each sporangium is annulate. In all of the species 
the sorus is circular and consists of 8-6 (10) pyriform 
sporangia which Zeiller describes as bearing a complete 
transverse annulus. 
Stur® believed that the ‘‘annulus’” is merely a type 
of preservation of the exannulate sporangia. Solms-Lau- 
bach’ agreed with the opinion of Stur and went further 
in saying, ‘‘l am. still obliged to assent to Stur’s opinion 
of the independent existence of the annulus. If we look 
at the obliquely conical sporangium from above, we get 
a profile view of one or more transverse rows of the 
strongly thickened cell-walls, and may mistake them for 
an annulus: but we find that whenever we alter the posi- 
tion of a detached sporangium, the supposed annulus 
appears in another place.” 
This annulus is not clearly understood. Kidston found 
that the annulus may be biseriate or triseriate, although 
earlier work indicated that the annulus was uniseriate. 
It has been implied that if Kidston’s observations prove 
to be typical for most (if not all) species of Oligocarpia 
then their affinity with the Gleicheniaceae may be chal- 
lenged. However, it is to be observed that in only a few 
species of Oligocarpia is the sorus known and Kidston’s 
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