174 A CONTRIBUTION TO, ETC. 



ficult to meet with perfect specimens at all seasons. Brown 

 mentions this fern as being closely allied to Davallia or Dicksonia 

 dubia (Hooker), so common in this neighbourhood. The chief 

 points of difference appear to be the delicate texture of the frond, 

 the paucity and somewhat marginal character of the sori, and the 

 better defined forking of the veins. The other tree ferns are Also- 

 pliila Australis, and A. Leichhardtiana. The latter, which may be 

 distinguished by its darker rachis and serrated segments, is not 

 noticed in Sir William Hooker's " Species Eilicum ;" and it is 

 somewhat remarkable that that eminent writer speaks of A. Aus- 

 tralis, so abundant on the mountains, as " probably a rare species," 

 remarking that the only specimens he was so fortunate as to 

 possess were amongst Sieber's collections ! The genus Folypo- 

 dium has two species plentifully distributed amongst the larger 

 ferns, and they may frequently be seen twining round the cau- 

 dices of the tree ferns, or spreading over the rocks. These are 

 P. Billardieri and P. rupestre, and P. attenuatum has been found 

 in an adjacent gully. P. Billardieri, or, as it is sometimes called, 

 P. scandens, is a very variable fern, the fronds of which are some- 

 times simple find sometimes pinnatifid the former being fre- 

 quently in a fertile state as well as the latter. Of the genus Asple- 

 nium, A. odontites (Brown) is very common on the trees at Tomah ; 

 and A. nidus and A. flabellata occur in the neighbourhood, and I 

 have been informed that A. dlffbrme has been found in the same lo- 

 cality. Connected with this genus, and perhaps unnecessarily sep- 

 arated from it, is Allantodia tenera, a very delicate fern, now placed 

 in the genus Asplenium, and frequently growing in company with 

 Dicksonia davallioides. The genus La-mar ia or Stegania, which has 

 three species at or near Tomah, viz., L. Pater soni, L. lanceolata, 

 and L. procera, occasions some difficulty to the pteridophilist 

 from its resemblance to the genus Blechnum. Indeed the two 

 genera are not in some species easily separated, unless we adopt 

 Smith's canon, "that from Lomaria, the genus Blecknum differs 

 not only in its' fertile fronds not being contracted, but also in the 

 venules being continued beyond the soriferous receptacle and ter- 

 terminatiug in the margin." Adopting this view, I think that one 

 so-called species of Bleclmum common on the creeks near Parra- 

 rnatta, must be referred to Lomaria, as the fertile fronds are 

 certainly contracted, In addition to the ferns enumerated, Gram- 



