90 HOOKERIA. 



specimens to us in the year 1815. No one on examining 

 with the slightest degree of attention its leaves can have anyj 

 difficulty in distinguishing it from H. lucens; and even the 

 whole plant, in its smaller size, brighter green colour and 

 more membranaceous foliage, is sufficiently striking. It| 

 is not with the other British species that it can ever be 

 confounded ; but with the figure of Leskea albicans (an 

 undoubted Hookeria) there is so perfect an accordance, 

 that few would venture on pronouncing them different 

 species without as cautious a comparison with authentic 

 specimens as we have ourselves made. In L. albicansA 

 however, the colour is very much paler, and has given] 

 rise to the specific name ; the leaves are of a thinner! 

 texture, and furnished with reticulations so very large, 

 that when a leaf of each is seen on the table of a micro- \ 

 scope at the same time, a tyro in the science would say 

 that they could not belong to the same species. More-] 

 over in L. albicans the margin of the leaf is thicker, and! 

 the leaves are much more deeply serrated. In other respects] 

 the foliage perfectly accords. But there appears a difference! 

 in the operculum, which is shorter in the L. albicans, and! 

 the calyptra is not only of a different texture, but cleft at 

 the base like the veil of a Trichostomum or a Grimmia.l 

 We are aware how difficult it is to form characters, in a] 

 few words, to separate plants so closely allied; and wej 

 should not be disposed to differ much from those who, after] 

 a due investigation of the characters in each species, might] 

 choose to consider them varieties arising from difference of | 

 soil and climate ; the one being found on the trunks of de-J 

 caying trees in Jamaica, the other in the cold bogs of Ire-?! 

 land. 



There is still another plant which we cannot pass over inj 

 silence, since in the form of its leaves, and its two nerves! 

 and mitriform calyptra (making it a Hookeria), there is the] 

 most perfect conformity. We mean the Leskea depressa of I 

 Swartz and Hedwig, and a native also of Jamaica. Butl 

 this is a smaller plant ; its surculi, though depressed, have] 

 not the leaves so decidedly bifarious, nor are these latter! 

 nearly so strongly reticulated; their margin is not thickened,) 

 nor at all serrated ; and the lid of the capsule is shorter. 



