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conveys an idea of all that is eminent in Pteridology, arrived at the 
conclusion that the involucre did not afford satisfactory characters ; 
and he consequently sought, and believed he had found, in the dif- 
ferent distribution of the veins, diagnostics which would make the 
subject simple and intelligible. After vindicating the importance of 
veins generally in all plants, and comparing them to the skeleton of 
vertebrate animals, he goes on to assert their paramount importance 
in ferns. “Hac vasa in organis foliaceis Filicacearum tanquam 
coste, venz et venule palam fiunt, et ex supra allatis causis maxi- 
mum in describendis dividendisque Filicibus possident argumentum. 
Filicacez compage venarum anatomica ab omnibus aliis vegetabilibus 
phanerogamis quam maxime differunt; hac ex causa vene Filicacea- 
rum characterem essentialem et validissimum ex interna structura 
harum plantarum desumtum prebent.” Pres], also, was well ac- 
quainted with the diversified structure of the rhizome, and with the 
previous observations of Link, Moh), Gaudichaud and Treviranus, 
only one of whom I have cited, because the others have not so me- 
thodized their researches as to render them available for classification. 
Presl writes thus on the “caulis:”—% Caulis Filicacearum, induat 
nunc formam rhizomatis nunc caudicis, componitur e textu celluloso re- 
gulari ac magno parenchymatoso et prosenchymatoso vasa involucrante, 
Vasa hee constituuntur e vasis scalariformibus et porosis paucis cellu- 
lis parenchymatosis intermixtis, et strato cellularum prosenchymatosa- 
rum plerumque parietes crassas possidentium in provectiore etate ut 
plurimum fuscarum vel atrarum nitentium includuntur et a parenchy- 
mate adjacente cryptas rubra materie repletas continente dividuntur.” 
The entire passage is not germane to the question of employing the 
mode of growth as a character, but is happy in showing that this 
great master fully appreciated the difference between a rhizome and 
a caudex. 
in taking leave of Pres] it is necessary to state that his system is 
framed on a combination of characters, the venation being the promj- 
nent feature. He makes five orders, under the names of Filicacex, 
Hymenophyllacee, Maraitiacez, Osmundacee and Ophioglossacea. 
JoHN SMITH, 1854. 
Mr, John Smith, of the Royal Botanical Garden at Kew, has for 
many years entertained the idea that the mode of growth in ferns 
should be employed in their classification. Although his views did 
not for some time receive the stamp of authenticity given them subse- 
quently, by publication under his own name, yet it was well known 
VOL. V. 26 
