LASTR/EA DILATATA. 145) 
leaflets; the stalks of the leaflets, also, are slightly 
scaly. The leaflets are rather alternate than opposite, 
and the leafits are, for the most part, also alternate. 
Fructification numerous, and nearer the midrib than 
the edge of each leaflet ; at first swollen and kidney- 
shaped, hut the cover (indusium), when burst, becomes 
circular, with a deep cut in its lower side. 
We have observed how much this Fern varies in 
form, and the best particulars relative to this character- 
istic are the following by Mr. Francis: 
" If it grow in a situation which is wet in the spring and 
dried up in the summer, as on the margin of a pond, it will 
become var. /3, very dark, large, and quite drooping. Con- 
tinued wet will elongate the leaf and separate the pinnae and 
pinnules as in var. 7. A young plant is only twice pinnate 
and flat. A dry and rocky, or a confined situation will 
render the leaf small and less divided, the pinnules blunt, 
deflexed, and drooping : thus starved it becomes the Aspidium 
dumetorum of Smith (var. 5). I know not the nature of the 
habitats in which the recurved var. (e) of Bree grows. [It 
is said to grow both in dry and wet shady places, preferring 
moisture. But all the recorded localities are in damp 
climates. ED.] The varieties recurvum and dumetorum are, 
I believe, not altered by cultivation, and Sir J. E. Smith 
implies, in his description of the latter, that its spores 
produce the same variety. 
a (dilatatum). Frond sub-tripinnate, triangular, ovate. 
Pinnules petioled. 
j8 ( ). Frond tripinnate, deflexed, triangular. 
Pinnules convex. 
7 ( ). Frond tripinnate, triangular, elongated. 
Pinnules somewhat decurrent, and dis- 
tant from each other. 
