206 
154 
Veins all free or the lower 1—3 pairs united and sending an 
excurrent vein towards the sinus; in some species the lowermost 
pair (rarely the two lower pairs) is meniscioid, i. e. the excurrent 
branch being interrupted before reaching the next pair of ana- 
stomosing veins. 
4. Indusium persistent. Lower veins connivent to sinus, rarely 
truly united. Lower pinnz mostly with a cuneate base 
(D. biformata excepted). 
5. Sori near the margin. 
6. 
Lamina coriaceous, glabrous; pinne scarcely incised !/s. 
Indusium reniform, whitish, glabrous. 
251. D. paucipinnata (Donn. Smith) Maxon. 
Lamina thinly membranous, hairy on the ribs; pinne 
incised about !/». Indusia reniform, athyrioid or asple- 
nioid in the same pinna or even segment. 
254. D. Schaffneri (Fée) C. Chr. 
5. Sori medial. 
6. 
6. 
Basal pinne not cuneate at base; fertile pinnz and 
segmertsucontracted me TED 239. D. biformata Ros. 
Basal pinne with a long cuneate, entire base; fertile 
pinnz and segments not contracted. 
7. Indusium small, setose. Veins 12—14. Andes. 
249. D. tristis (Kze.) O. Ktze. 
7. Indusium large, nearly glabrous. Veins 9—11. South 
Brazil’ «.— tc eee m en re ue 253. D. cuneata n. sp. 
4. Indusium none or minute, rarely found. 
5. Under surface without minute stellate hairs on costule 
and lea[-tissue. 
6. 
Lower 2—4 pairs of veins connivent to sinus, only oc- 
casionally the lowermost pair is united. 
7. Smaller plant: pinnz: 2—4 to each side, serrulate, 
densely warted on both surfaces...... 258. D.juruensis n. sp. 
Larger with about 10 pairs of pinnz, not or incon- 
spicuously warted, more deeply cut. 
8. Lower pinne with a long cuneate, entire base, 
incised about halfway down; 2 pairs of veins 
connivent to sinus. Sori medial.. 249. D.tristis (Kze) O. Ktze. 
8. Lower pinnze lobed to the very base, scarcely 
incised to the middle; 3—4 pairs of veins con- 
nivent to sinus. Sori inframedial or about medial. 
9. Rachis upwards and coste beneath densely 
tomentose; upperside strigose. 243. D. lugubriformis Ros. 
9. Rachisand coste beneaht glabrous or nearly so. 
10. Leaf papyraceous, light-green; costze and 
costules prominent, stramineous. Lower 
pinne not reflexed. 
11. Pinnz 2 cm broad, crenate or slightly 
lobed; veins 3—5 jugate. Rachis gem- 
miferous, glabrous. 256. D.straminea(Bak.) C. Chr. 
11. Pinne 3 cm broad, lobed halfway 
down, veins 12—18 to a side. Rachis 
minutely pubescent, not gemmiferous. 
250. D. nicaraguensis (Fourn.) C. Chr. 
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