TAB. LXXXI. 
Trichomanes Spruceanum* Hook. 
Frondibus difFormibus rigido-membranaceis bipinnatifidis, lobis 
primariis oblongo-ovatis obtusis secundariis bi-trifidis, 
racbibus subtus longe hirsutis sterilibus brevi-stipitatis 
latissime ovatis lobis imbricatis, fertilibus longissime stipi- 
tatis contractis oblongis obtusis* involucris cylindraceis in 
loborum apices omnino immersis* columna inclusa* stipitibus 
alatis, caudice longe repente setaceo-squamoso. 
Hab. San Gabriel- catingas, Rio Negro, a tributary of the 
Amazon, June 1852* Spruce * n. 2334.* 
No one can fail to see a great similarity between the 
Trichomanes heteropliyllum , H.B.K., figured by Kunze* Fil. 
2. t. 109. and this; but they are truly distinct: our plant 
is nowhere pinnate, and the lobes both of the sterile and 
fertile fronds are very different in form and much more 
divided; the involucres are different in shape* and the columella 
is here included. Still the two unquestionably belong to the 
same natural group* differing from what we call the subgenus 
ie Hymenostachys” (see Gen. et Sp. Fil. 1. p, 114), which has 
a reticulated venation* the involucres arranged in a simple 
distichous spike, and connate; and from the subgenus Feea 
(l. c.) which has the involucres also arranged in a simple 
distichous spike and the veins all free : — whereas in our plant 
and in Tr. heterophyllum 3 Humb. the fertile frond is not 
converted into a spike* but is merely a contracted form of 
the common frond. In all* the fertile stipes is very much 
elongated (here beautifully winged), and the sterile one 
very short. 
Fig. 1. Portion of a sterile frond, f. 2. Portion of a fertile 
ditto, f. 3. Involucre: — magnified. 
