257 Journal of Travel and Natural History 



been manufactured out of some of the common ferns with a wide 

 geographical area is perfectly astonishing. Osmunda regalis, an 

 extreme case, for it is so striking and well-marked a plant, and so 

 widely dispersed in Europe that it is certain to attract the notice 

 of any person who pays attention to plants early in their botanical 

 career, has received between ten and twelve specific names, given 

 to it most of them by authors of high repute who have received the 

 plant from some distant country, and named it afresh upon the 

 principle that their old familiar acquaintance could not possibly 

 have strayed so far. If it has fared so with the Osmunda, what 

 can we expect with the widely-diffused species of the less clearly- 

 marked large Polypodial genera, such as Aspidium (Polystichum), 

 aculeatum, and Cystopteris fragilis ? But we cannot impute any 

 fault of this kind to the author of the work before us, and hence its 

 merit. Dr Milde has carefully examined and compared together 

 his specimens from over a wide geographic range without allowing 

 himself to be biased by preconceived ideas of the kind to which 

 we have alluded, and has, moreover, taken great pains to acquaint 

 himself with, and to procure a sight of authentic specimens of the 

 numerous species (a large proportion of them bad ones) which 

 have been published during the last twenty years in the various 

 continental journals and bulletins, and it is a great boon to the 

 general student to have these all brought together into one view, 

 and to have them described and revised (revision meaning in a 

 large number of cases annihilation) by so good an authority. 



We do not consider Dr Milde's scheme of fern-classification, so 

 far as it possesses any novelty, an improvement upon the old 

 methods. He divides, in the first place, the Filicoid plants into 

 four, what he calls, families — Filices, Equisetacea^, Lycopodiaceffia, 

 and Rhizocarpere. These, we consider, may be fairly regarded as 

 divisions equivalent to the natural orders of flowering plants, and 

 we suppose that Dr Milde views the matter in the same light, as 

 he calls his next divisions sub-orders \ but if so, it would have 

 been much better to have used the ordinary nomenclature. Filices 

 he divides into five sub-orders — Hymenophyllese, Polypodiaceoe, 

 Cyatheacere, Osmundace?e, and Ophioglossere. To this we have 

 nothing to object, except that it is better to keep the termination 

 acece for orders. He draws a distinction, which is quite a sound 

 one, between a true indusium or involucre, quite distinct from the 

 surface of the frond and destitute of stomata, and a false indusium 

 passing insensibly into the parenchyma of the pagina, and fur- 

 nished with stomata on the under surface. This is quite satisfac- 



