ONYCHIOPSIS. 41 
recent genera Onychium and Gymnogramme, especially of the 
former. The original diagnosis of the genus Onychiopsis, with 
reference to a single species, O. elongata, is as follows! :— 
‘‘Fertile segments different from the sterile. Sori terminal, 
linear, on each side of the midrib, parallel with the margin, 
involucrate; the involucrum of each side confluent over the 
midrib.” 
So far as I have been able to discover, this is the first record 
of Onychium among fossil ferns. According to the ‘Synopsis 
Filicum,”? the genus occurs at the present time in Northern 
India, China, Japan, Java, Persia, Abyssinia, and Malayan Pen- 
insula and Islands, ete. 
The more detailed examination of the points of agreement 
between the fossil species and the living genus will be attempted 
in the description of the two species Onychiopsis elongata (Geyl.) 
and O. Mantelli (Brong.). 
1.—Onychiopsis Mantelli (Brongniart). 
1824. Hymenopteris psilotoides, Stokes and Webb, Trans. Geol. Soe. ser. ii. 
vol. i. p. 423, pl. xlvi. fig. 7. 
1825. Hymenopteris psilotoides, Sternberg, Flor. Vorwelt. iv. p. xxii. 
1827. Hymenopteris psilotoides, Mantell, Illust. Geol. Sussex, p. 55, pl. i. 
3a and 3); pl. iii. fig. 6? and 7; pl. iii.* fig. 2. 
1828. Sphenopteris Mantelli, Brongniart, Prodrome, p. 50. 
Sphenopteris Mantelli, Brongniart, Hist. vég. foss. p. 170, pl. xlv. 
figs. 3-7. 
1833. Sphenopteris Mantelli, Mantell, Geol. S.E. England, p. 241. 
1833. ? Sphenopteris Sillimani, Mantell, Geol. 8.E. England, p. 239. 
1836. Cheilanthites Mantelli, Géppert, Foss. Farnkrt. p. 231, Nova Acta 
Ac. Caes. Leop.—Car. vol. xvii. Supp. 
1838. Sphenopteris Mantelli, Sternberg, Flor. Vorwelt. vii. p. 56. 
1839. Cheilanthites denticulatus, Roemer, Verstein. Ool.-Geb. p. 9, pl. xvii. 
fig. 1. 
1843. Cheilanthes (Sphenopteris) Mantelli, Dunker, Progr. p. 5. 
1845. Sphenopteris Mantelli, Unger, Syn. plant. foss. p. 59. 
1846. Sphenopteris Mantelli, Dunker, Wealdenbildung, p. 2, pl. i. fig. 4a. 
1846. Sphenopteris Rémeri, Dunker, loc. cit. p. 3, pl. i. figs. 8, 4 and 5. 
1846. Sphenopteris tenera, Dunker, loc. cit. pl. viii. fig. 5. 
1846. Confervites fissus, Dunker, Joc, cit. pl. i. fig. 1. 
1848. Sphenopteris Mantelli, Bronn, Index Pal. Nomencl, p. 1169. 
1 Yokoyama, Joc. cit. p. 26. 
2 Hooker and Baker, p. 143. 
