II. ALLOSOBCS. 
59 
The Rock Brakes has a short decumbent caudex, pro- 
ducing numerous fibrous roots, and a tuft of adherent 
fronds from its crown. The young fronds spring up in 
May and June, and attain ma- 
turity by the end of the summer, 
disappearing at the commence- 
ment of winter. They are nearly 
triangular in outline, and from 
four to eight and sometimes 
twelve inches high. The stipes 
is long, slender, pale-coloured, 
and smooth. The barren fronds 
are bi-tri-pinnate, the pumas 
[Allosorus crispns.] 
pinnules and lobes being all alternate ; the ultimate 
divisions are wedge-shaped and cleft, or oblong-oval 
with an even sinuously-toothed margin; or sometimes 
