HARDWICKE'S SCIENCE-GOSSIP. 



149 



removal of many thousands of feet of Silurian rocks. 

 What a vista of time does not this present to the 

 imagination ! But to read about these denudations 

 is insufficient ; it is necessary to walk about, map in 

 hand, to thoroughly realise their meaning. It is then 

 that geology becomes a living fact, a sublime thought 

 before which historical ideas of time and action are 

 mere fugitive shadows. Being brought face to face 

 with such facts cannot fail to profoundly influence 

 our ideas of the relation in which we stand to Nature. 

 There are many aspects in which these relations may 

 be viewed, they have been dwelt upon by the great 

 minds of all ages ; but not the least awe-inspiring, if 

 bewildering, is the panorama of creation which 

 geology only within the last fifty years has unfolded, 

 and vaguely in broad outlines pictured to the human 

 eye. 



specially transformed. In some there is a thin inner 

 membrane turned up to meet the proper indusium. 

 This forms a connecting link with Lindscea. 



P. aquilina, Linn., or common brake, is the only 

 species with the double indusium found in the 

 island. Surely no description of the fern is necessary 

 for English people, living as they do, and bearing 

 with them to foreign lands the recollection of the 

 homes of their childhood ? Brake is found all over 

 the hills and in every part of the island. 



P. nemoralis, Willd. (or quadriaurita, Retz.), is still 

 more abundant, especially in the town of Victoria. 

 This species is twice or bi-pinnate, and easily 

 distinguished, as the lowest pinnse on each side of the 

 rachis are in twos, and hang down, a habit common 

 to the order, and no doubt suggesting the name from 

 the likeness to a bird's wing (pteron — a wing). 



Fig. 96. 



-Pteris scmi-pinnata, 

 Linn. 



and 



Ftcris serrulata, Linn., sterile 

 and fertile fronds. 



Fig. qj.—Asj>Ienium (Dipl.) Jafonkum, 

 Thunb. 



SOME FERNS OF HONG KONG. 

 By Mrs. E. L. O'Malley. 



[ Con tin uedfrom j>. 134.] 



Gen. VII. Pteris, Linn. 

 {Brake.) 



ALL the species of this large genus by no means 

 resemble Pteris aquilina, or eagle fern, so called 

 in some counties from the supposed likeness, as every 

 boy knows, to a spread eagle, in the vessels of the 

 stalk cut traversely ; but in all, the covering of the 

 sori is marginal and continuous. It runs along the 

 entire length of the leaf, and consists of the margin 



P. longifolia, Linn., or long-leaved pteris, is a large 

 fern, fond of heat and dry dusty places, simply 

 pinnate, except the two lowest pinnre, but all the 

 pinnce narrow straggling and long. An untidy- 

 looking fern, and one which might at first sight be 

 mistaken for Blechnum orientale, but the sori placed 

 at the edge, instead of down the centre of the leaf- 

 segment, at once mark a different genus. In pteris, 

 the extreme point of the segment is always destitute 

 of sori, a peculiarity we do not observe in ferns of 

 other genera. Two more species are common, both 

 smaller and more delicate in texture. 



P. semi-pinnata, Linn., or half-pinnate pteris, is 

 one of the commonest plants in the island, and very 



