—54— 



by the law of priority must bear the name Dryopteris. If, as many 

 believe, these ferns should be further grouped according to the 

 shape and attachment of the indusium and the methods of vein- 

 ing into two or more generic groups, the name Dryopteris must 

 stand for that group, larger or smaller, which contains the male 

 fern {Poly podium filix-mas of Linnaeus) since this is the type of 

 Dryopteris of Adanson. 



After Adanson, Schott was perhaps the next to use the name 

 Dryopteris in his Genera Filicum C1834)*, and Asa Gray used it 

 in the first edition of his manual (1848), including in it Dryopteris 

 Thelypteris. D. Noveboracensis, D. intermedia* D. dilatata, D. 

 rigida (with which he confused D. Boottii), D. cristata, D. 

 Got die ana, and D. marginalis ; later still Otto Kuntze (1890) 

 used it in his Revisio transferring all the species given in "Synop- 

 sis Filicum." 



Later writers established other genera for various groups of 

 the ferns with superior circular or reniform indusia in the follow- 

 ing order: Polystichum Roth (1799), Tectaria Cavanilles (1799), 

 Aspidium Swartz (1801), Nephrodium Richard (1803), Lastrea 

 Bory (1824), Sagenia Presl (1836), Phanerophlebia Presl (1836), 

 Cyrtomium Presl. (1836), and several others, but space will not 

 permit their discussion here. It is sufficient to add that the study 

 of the historical literature of the ferns is not only highly interest- 

 ing, but its careful perusal will often prevent us from making 

 serious blunders. 



Another question of proper nomenclature is involved in the 

 various forms of the common brake which the editor has recently 

 well characterized. We will not refer either to the generic name 

 or to the number of species involved, concerning both of which 

 questions there will be differences of opinion. In accepting a 

 name it must first be determined to what plant the name was 

 originally applied. This often requires access to a large library 

 of fern literature. If the plant is not American or if its range ex- 

 tends to the tropical regions of America, even, access to a large ar- 

 ray of material is necessary. Such an array is not yet accessi- 

 ble in any American collection, even the best; hence the necessity 

 of supplementary study of the Kew, Berlin and Paris collections, 



* Those who advocate the absurd "fifty year" principle which makes a 

 genus good if somebody happened to use it in a "reputable work" f o rty- 

 nine years after it was first established, but not if it happened to be fifty- 

 one years before it was so used, will rind here a loop-hole through which 

 they may crawl in order not to use Dryopteris. But even this will not en- 

 able them to use either Aspidium or Lastrea, as the context shows. 



