^c "MB CHARACTERS OF TRIRES AND GENERA. 
j bringing about their extermination in this country. 
** Vernation fasciculate, decumbent. 
T. crispum, Linn. (v v.); T. pinnatum, Hedw. (v v.) ; T.. 
lucens, Sw. ; T. Lambertiana, Hook. ; T. attenuatum, Hook. 
(v v.); T. alatum, Sw. (v v.); T. Baneroftii, Hook. (v v.); 
T. crinitum, Sw. (v v.) ; T. superbum, Back. (v v.) 
*** Vernalion fasciculate, erect. 
T. javanieum, Bl. (v ei: T. Leprieurii, Kunze. (v v.); 
T. rigidum, Sw, (v v.); T. fceniculaceum, Bory (v v.); T. 
meifolium, Bory (v v.); T. polyanthos, Hook. Ic. PL, t. 708; 
T. strictum, Menz.; T. gigantum, Bory; T. Smithii, Hook. ; 
T. elongatum, A. Cunn. (v vi: T. saxatile, Moore (v v.); 
T. trichophyllum, Moore (v v.); T. setigerum, Back. (v v.) 
Oss.—I have above shown that the only technical 
difference between Hymenophyllum and Trichomanes is that 
in the latter the receptacle is prolonged beyond the spo- 
rangia, even in some to the length of a quarter of an inch, 
having the appearance of bristles excerted beyond the ` 
margin of the frond. 
In this country Hymenophyllacee is represented by three- 
species, namely, Hymenophyllum Tunbridgense, H. unilaterale, ` 
and Trichomanes radicans, They are, however, very rare, 
being found in a few special localities; the latter is becoming 
very rare in England, but is found in several localities in the ` 
 SOuth of Ireland. Since the invention of Wardian cases, 
- these “ Filmy Ferns ” so called, have become great favourites - 
with amateur eultivators; and the great demand for them ` 
With regard to Exotie species, in my “Catalogue of. 
Cultivated Ferns” for 1846, only two species are enume- 
~ rated, which in 1864 had increased to sixty-three, as 
.  'ecorded in “Ferns, British and Foreign,” pages 240 and 
