FLORA OF 11 IF KOOTAMF FOK^F\TI()^■. 2;»3 



soparalioii as even a \;ni(My. These pinnules ai'c coiniuoiil}- longer 

 and naiTowef. especially toward theii- tips, which nai'row more gradually 

 than those of the \'irginia ])lant. They are also more acute. Xo foi'ms 

 wer(^ found in the \'irginia specimens that showed any indication of 

 undulation oi' lohing. Although these differences ai"e slight, and hence 

 of no great weight, it secMUS to he the hetter usage, in the case of ])lanls 

 that grew in widely sepai'ated localities, to allow them inoi'e weight 

 in separating than in uniting forms. The presumption is that the plants 

 are different, and the burden of proof is with the person who would 

 unite them. Nonessential features that are not admitted as justifying 

 lh(^ formation of new species cert.ainly can not he taken as establishing 

 the identity of plants that grew in situations sepai'ated by thousands 

 of miles. Still less can such featvu'es l)e admitted as indicating iden- 

 tity, when the plants grew in different times. Then, too, if the new 

 species oi* variety turns out to be identical with some known form it 

 is easier to drop its name than to restore it to indepentieuce when it is 

 shown to have been improperly merged with some previously described 

 plant. 



PI. LXXl, Fig. 14, represents a i)ortion of a pinna carrying parts 

 of a mnnber of pinnules with undulate margins. It will give a good 

 idea of the size that the rachis of the piimu' attained, but unfortunately 

 the pinnules are not well enough preserved to gWe their full dimensions 

 and shape. Fig. 15 gives a portion of a crenately incised pinnule, which, 

 when entire, was evidently considerably longer than the specimen. 

 Some of the crenate pinnules found are wider than this by a half. Fig. 

 16 represents one of the lobes enlarged to show the nervation. Fig. 17 

 gives a fragment of one of the pinnie (H)ntaining a numbei- of normal 

 entire pinnules from the middle portion of a pinna and frond. Fig. 18 

 represents a ))innule of this magnified to show the nervation. A mnu- 

 bcr of the pimiules of this specimen show on theii' sui'face markings 

 that look strikingly lik(^ elli])tical sori. They are, however-, not placed 

 according to any dehnite plan, but occur on any part of the pinnule, 

 sometimes on different nerves and on different parts of them and some- 

 times l)etween the nerves. They ai'e probably due to some fungoid 

 disease. Fig. 1'.) shows the terminal j)or'tion of a piinia, with the dimi- 

 mition in tli:it pai't of the size of the pinnules and their' increasing con- 

 solidation towar'd the ends of the pirma\ 



