BERRY: FERN GENUS CLATHROPTERIS 283 
third the distance above the base, and have an indicated length 
of about 30 cm. They taper conspicuously proximad and are 
still free at a point where their width has narrowed to less than 
1.5 cm. Although their extreme bases are obliterated they were 
evidently either entirely separate or only slightly united. The 
margins are not entire but the marginal teeth are very much re- 
duced, even at a distance of 10 cm. above the base, and proximad 
they appear to have been entirely wanting, although the preser- 
vation is not sufficiently good to be positive on this point. 
It has been assumed by most students that the Clathropteris 
frond consisted of a single dichotomy and therefore had a habit 
somewhat like the modern Dipteris and more conspicuously like 
the existing Matonia pectinata, or like that of the extinct genus 
Dictyophyllum as restored by Nathorst. It would appear from the 
Virginia material that, in addition to such a group of what I 
have called primary pinnae, arranged en éventail, each branch of 
the dichotomy continued for some distance and then expanded 
into palmately arranged ultimate or secondary pinnae. These 
were fewer in number than those that I have called primary pinnae, 
being eight in the preserved material. They are wider and more 
conspicuously toothed and are clearly united for a distance of 3-5 
cm. above their bases in my material. 
While this interpretation is based in the first instance on ma- 
terial no longer extant and is therefore to be accepted with reserve, 
I feel justified in calling attention to it and in offering the tenta- 
tive restoration of this interesting species as shown in Fic. 2 
That the fronds were sometimes much larger than I have in- 
dicated is shown by fragments in my possession and by the 
extremely large fragments collected by F ontaine, which according 
to this author showed a width of pinnae of 20 cm. and an indicated 
length of 60 cm. 
I have seen no fertile specimens from Virginia, te certain 
foreign material shows, on the lower surface of the lamina, an 
abundance of crowded sori without indusia and made up of from 
five to fifteen annulate sporangia, similar to those of Dictyophyllum 
and Dipteris, although the annulus is said by Goeppert to have 
been complete—a feature that it would seem would be impossible 
to decide in the absence of structural material. 
