482 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



nerves. The soriis is placed uniformly upon the longest (outer) side of the 

 costal areole; otherwise the veins of the whole frond arc of equal rank; all 

 are discontinuous in direction, adjoining only at an angle. The venation thus 

 shows some approach to the type of Diplaziopsis; but in that genus, i\H iu 

 Hemidictyum, there are well-developed lateral nerves, lust in a network only 

 toward the margin. 



Species two : 

 Holodictyum ghiesbreghtii (Fourn.) Maxon. 



Asplcniuni ghicshrvghtii Fourn. Mex. PI. 1: 111. pL 5. 1S72. 



Described and figured from specimens collected by Ghiesbreght (ho. IG) on 

 wet rocks, Barranca de Tlacolula, Oaxaca, Mexico, 1842-43. This number is 

 represented in the TT. S. National Herbarium by a portion of a frond, 



Holodictyum finckii (Baker) Maxon, 



Asplenhtm finckii Baker, Ann. Bot, 8 : 12G. 1S04. 



Described from specimens at Kew, collected in the District of Cordoba, State 

 of Vera Cruz, Mexico, by Hugo Finck. Represented in the U. S. National 

 Herbarium by an incomplete frond recently received from Kew, this showing the 

 areoles to be in five or six series, not hi four as described by Mr. Baker. 



Christenseu has suggested that A. finckii, which apparently was founded by 

 Mr. Baker without regard to the earlier A. (ihic^brajhtli, may be identical 

 with the latter. To this the writer is at present unwilling to assent The 

 typo of venation in the two type specimens is the same, hut the areoles of finckii 

 are actually larger and rehitively broader; the sort diverge from the costa at 

 a greater angle and are shorter, those of ghicshrcghtil (according to Fournier) 

 even attaining a maximum length of one inch. Yet we refer to finckii excellent 

 specimens collivtei.1 from shady situations among rocks in a lt>ng deep canyon 

 near G6mez Farias, State of Taniaulipas, Mexico, altitude about 350 meters, 

 by Dr. Fdward Palmer (no, '^?>(\), April, 1007, which differ in their greater size 

 and higher average number of series of areoles and in having the sori rather 

 less divergent from the costa, this last character being iu tlie direction of ghics- 

 hrcghfiL Whether the differences noted among the three specimens are no 

 greater than should be accounted variations within a single species can not be 

 determined with certainty from the material at hand; but it seems reasonable, 

 on the strength of the characters mentioned above, to recognize for the present 



the two species already described. 



The upper and apical portion of a normal frond of Doctor Palmer's no. ;536 

 is shown in PI. LVI, Fig, 4, The i*hizome of the plant, though split in half, 

 lengthwise, yet carries fifteen fronds, wliich must be about half the original 

 number for the living plant. The fronds are about 40 cm. long and taper very 

 gradually from about their middle to a long attenuate base, being narrowly 

 winsred down to the rhizome. 



THE IDENTITY OF ASPLENIUM EHIZOPHYLLUM L. 



Three very different elements Avere merged in Linnaeus in 1753 

 under the name Asplenium Thizophyllum.^ The names under which 

 these have usually gone are: (1) Camptosorus rhizophyllus^ applied 



to the fern of the eastern United States, (2) Camptosorus sihincus^ 



restricted to an Asiatic species, (3) Fadyenia proUfera^ for a West 



''Not to be confused with the swond AspJcnium rlii:::ophyUum of Linuious 

 (Sp. PI. ed. 2. 1540. 1TG3), discussed at page 49U of the present paper. 



