Allgemeines. 631 



Bost. Jour. Nat. Hist. 1: 132 (1835); Crysopsis pilosa (Walt.) 

 Britton, Mem. Torrey Club, 5: 316 (1894), is a homonym oi 

 Chrysopsis pilosa Nutt. Jour. Acad. Nat. Sei. Phila. 7: 66 (1834), 

 and is to be rejeeted, notwithstanding the iact that Erigeron 

 pilosum Walt, was published in 17S8; Carex scoparia monili- 

 formis Tuckerm. Enum. Meth. Car. 17 (1843), and Carex strami- 

 nea moniliformis Tuckerm. loc. cit., can not both be maintained. 



b) A generic or subgeneric name is a homonym when 

 previously published, or proposed in print for another 

 genus. 



Examples. — Torreya Arn. Ann. Nat. Hist. 1: IrO (1838) is 

 a homonym of Torreya Raf. Am. Mo. Mag. 3: 356 (1818), of 

 Torreya Raf. Jour. Phys. 89: 105 (1819), of Torreya Spreng. Neue 

 Entdeck. 2: "J21 (1821), and of Torreya Eat. Man. ed. 5, 420 

 (1829); Rivularia Ag. Syn. Alg. Scand XXXVIII (1817) is a 

 homonym of Rivularia Roth, Cat. 1: 212 (1797); Nesaea Lzmour. 

 Nouv. Bull. Soc. Philom. 3: 185 (1812), is a homonym of Nesaea 

 Commers. ex Juss. Gen. PI. 332 (1789); Bulliarda DC. Bull. Soc. 

 Philom. 3 49 : 1 (1801), is a homonym of Bulliarda Neck. Elem. 2: 

 321 (1790). 



c) Similar names are to be treated as homonyms only 

 when they are mere variations in the spelling of the 

 same word ; or in the case of specific and subspeeifie 

 names, when they differ only in adjeetival or genitive 

 termination. 



Examples. — Penicillus and Penicillium, Callitriche and 

 Calothrix, Nemastylis and Nematostylis, Pterigophyllum and 

 Pteridophyllum, may be maintained; Cyathophora and Cyatho- 

 phorum, Asterocarpus and Astrocarpus can not be maintained. 

 Greeni and Greenii, may be maintained in the same genus : virginica, 

 virginiana and virginiensis, oregana and oregonensis, Hookeri 

 and Hookeriana, can not be maintained in the same genus. 



Canon 17. A name is rejeeted when there is an older valid 

 name based on another member of the same group (me- 

 tonym). 



Examples. — Meibomia Heist. ex. Adans. Farn. PI. 2: 509 

 (1763), is based on Hedysarum canadense L. Sp. PI. 748, and Des- 

 modium Desv. Jour. de Bot. II. 1: 122 (1813), is typified by Hedy- 

 sarum asperum Poir. Encycl. Suppl. 6: 408 (1804), consequently 

 if these species are regarded as congeneric the name Desmodium 

 is to be rejeeted; Boletopsis P. Henn. Nat. Pflanzenf. I 1 **: 194 (1899), 

 cannot stand as a genus to include a section bearing the name 

 Bolelinus Kalchb., the latter having been established as a genus 

 in 1877; Sisymbrium altissimum L. Sp. PI. 659 (1753), Sisymbrium 

 Sinapistrum Crantz, Stirp. Austr. ed. 2, 52 (1769), and Sisymbrium 

 pannonicum Jacq. Coli. 1: 70 (1786), have different types, but if 

 these are regarded as belonging to the same species, the two later 

 names are metonyms of that of Linnaeus. 



Canon 18. A name is rejeeted when there is an older valid 

 name based on the same type (typonym). 



Examples. — Miegia Pers. Syn. 1 : 101 (1805), is a typonym 

 of Arundinaria Michx. Fl. Bor. Am. 1 : 73 (1803), both being based 

 on the same species; Asplenium Vincentis Christ, Bot. Jahrb. 24: 

 109 (1897), is a typonym of A. Guildingii Jenm. Gard. Chron. III. 

 15: 70 (1894), both being based on H. H. Smith 's no. 1346 from 

 St. Vincent. 



Canon 19. A name is rejeeted when the natural group to 

 which it applies is undetermined (hyponym). 



