Benedict: Revision of the genus Vittaria 393 



features of scale differences and to have made several species 

 from what should properly be included in only one. Mettenius* 

 and Luerssenf described and figured accurately some of the im- 

 portant differential characters of leaf outline as seen in section, 

 but neither writer covered many species. More recently Jeffrey! 

 and Mrs. Britton and Miss Taylor§ have described and figured 

 carefully the morphology of one or two species each. The present 

 paper represents an attempt to describe and figure as thoroughly 

 as necessary the differential characters of the seven species included 

 in the subgenus Radiovittaria, as I have recently described it. 

 As has been noted, these seven species are all American. 



The work of which this paper, as also the earlier paper on the 

 genera of the tribe Vittarieae, is a partial report, has been carried 

 on intermittently during the last six years at the New York 

 Botanical Garden. The present article was brought nearly to 

 completion during a month's residence as research scholar during 

 parts of November and December, 191 1, also at the N. Y. Botan- 

 ical Garden, and I am glad to acknowledge my indebtedness to 

 Dr. N. L. Britton for the opportunities of study thus afforded.. 

 In general the material studied has been sufficiently cited in my 

 earlier paper on the genera of the tribe, but important additional 

 material has been received from the collections of Mr. W. R. 

 Maxon in Panama, and I have also been greatly aided by Mr. 

 Maxon's descriptions of the field conditions under which his 

 material grew. 



The present paper deals with less than one fifth of the total 

 species of Vittaria, but in order that the problems of the characters 

 and nomenclature may be clear at the start, a description of the 

 genus and its synonymy are included and also a discussion of its 

 division into subgenera. 



VITTARIA J. E. Smith, Mem. Acad. Turin 5: 413. pi. 9. 1793 



(Type species Pteris lineata L.) 

 Haplopteris Presl, Tent. Pterid. 141. 1836. 



*Fil. Hort. Bot. Lips. 25-27. pi. 27, f. 21, 22. 1856. 



tSchenk & Luerssen, Mittheil. Bot. 1: 57- pi- iz-19. 1871. 



J Phil. Trans. Roy. Soc. London 195 B: 1 19-146. pis. 1-6. 11 Je 1902. 



§ Mem. Torrey Club 8: 185-211. pi. 28. 1902. 



