IG. IIYxMENOPIIYLLU-M. 57 



down, furnished only with a central costa and a few faint irregular free spurious 

 vtnules, the margin not thickened ; sori solitary, terminal, the cuneate base 

 sunk in the frond^ divided about halfway down ; valves rounded, entire.— /)'«X.cr, 

 in Linn. Proceed. U. />. 3-iO. tab. 8. fig. E. Trichomanes niicrophylluni, Kalin. 



Hab. Moulmein, Rev. C. S. Parish.— The smallest :ind simplest species of the genus, 

 rivalling in minuteness Trichomanes Barklianum and vilicnse. 



3. II. marginatum, Hk. & Gr. ; st. 2-4 lin. 1. ; fr. linear, once or twice forked, 

 about 1 in. I., 1 lin. hr., furnished with a central costa ; texture firm ; margin 

 bounded by a thickened line, the apex emarginate ; sori terminal, solitary, sub- 

 orbicular, "divided down nearly to the base, with convex entire va^ye^. — Ilk.S Gr. 

 Ic. Fit. t. 34. Hk. Sp. 1. p. 87. Pachyloma, V. D. B. 



Hab. Port Jackson, Australia, rare.— Substance of the frond undulated. 



\/ 4. H. asplcnioides, Sw. ; st. 1-2 in. 1., slender ; fr. 2-4 in. 1., hy |-1 in. br., 

 pendulous, oblong in general outline, pinnatifid to within a short distance of 

 the rachis ; lower lobes rhomboidal-cuneate, cleft on both sides or one only ; 

 upper lobes simple, linear-oblong ; sari 1-4, terminal on the segments of the 

 lobes; invol. orbicular, free, cleft nearly to the base. — Ilk. Sp. l.p.87. Ic. 

 PL t. 957. 



Hab. Tropical America, from Cuba and ilexico southward to Brazil. — Easily recog- 

 nizable by its peculiar habit of growth. 



** Fronds glabrous, one to four times pinnatifid. — Sp. G-30. 



.5. H. abruptiim. Ilk. ; st. about | in. 1., very slender ; fr. \-\ in. \., j-\ in- br., 

 oblong, pinnatifid to within a short distance of the main rachis ; pinnae linear, 

 erecto-patent, about \ in. 1., 1 lin. l)r., sometimes dichotomously forked, only a 

 central midrib in each division ; sori 1 or 2 to a fi-ond, terminal on the apex or 

 upper segments ; invol. not divided more than halfway down, the base cuneate, 

 tb.e valres rounded ; accept, occasionally protruded. — Hk. Sp. 1. p. 88. t. 31. B. 

 II. brevifrons, Kunze, 



Hab. Jamaica, Cuba, Guatemala, Venezuela, and Brazil. — Allied to H. rarum, but 

 the main rachis has a broader wing below, and the pinna? are at most simply forked. 



6. li. mnioides, Baker; st. not more than ^ in. 1., very slender ; fr. 1-2 in. 1., 

 J in. br., linear, once pinnatifid ; rachis winged tliroughout ; the segm. all 

 quite simple, linear, the lower ones slightly imbricated, erecto-patent, 2 lin. 1,, 

 \ lin. hr, the upper ones pressed close to the rachis and much imbricated ; sori 

 solitary on three or four of the upper segments, large compared with the size of 

 the plant, divided about halfway down, the base campanulate ; valves more than 

 half a circle, large, membranaceous. 



Hab. New Caledonia, Pic du Mont Mu, Deplanche. — A minute moss-like plant, with 

 the habit of 31nium unchdatum or serratum, but dark-brown in colour. It is allied to 

 the preceding and the following, but whilst the segments are quite simple, the main 

 rachis is scarcely winged below. 



7. 11. tenellum, Kuhn ; rhizome wide-creeping ; st. 1 in. or less 1., slender, 

 naked ; fr. 1-2 in. 1., |-1 in. br., oblong-deltoid, tripinnatifid ; main rachis winged 

 doA-n to the base ; pinnce 4-G-jugate, deltoid, cuneate-truncate at the base on the 

 lower side ; lower pin7il. 1-2, cleft at tip with ligulate blunt lobes | lin. br. ; sori 

 2-C to a pinna, terminal in the lobes ; surfaces naked ; inv. with hemispherical 

 lobes and a cuneate entire immersed base. — H.emersum, Baker, Sj/n. Fil.edit. 1. 

 p. 457. Adiantum tenellum, Jacq. Coll. t. 21. fig. 3. 



Hab. Ceylon and Mascaren Isles.— Has nothing to do with H. tenellum, D. Don, 



H 



