626 Allgemeines. 



3. Priority of publication is a fundamental principle of bo- 

 tanical nomenclature. Two groups of the same category 

 cannot bear the same name. 



Note. — Previous use of a name in zoology does not pre- 

 clude its use in botany. 



4. The application of a name is determined by reference 

 to its nomenclatorial type. 



Part II. Canons. 



Section I. Categories of Classification. 



Canon 1. Connected or coherent groups of individuals are 

 termed species. 



Canon 2. Species are grouped into genera; genera into tribes; 

 tribes into families; families into Orders; Orders into 

 classes; classes into phyla. 



Note. — Order is preferable to cohort and phylum to division, 

 conforming to zoological usage. 



Canon 3. When additional categories are necessary for the 

 convenient presentation of relationships, they are to be 

 obtained by the recognition of intermediate groups, the 

 names of which are formed by prefixing sub- to the 

 names of the above principal categories. 



Examples. — Subspecies, subgenus, subfamily, suborder. 



Canon 4. Other terms, such as group, section, series, division, 

 and branch, may be used for more convenient temporary 

 arrangement under the above categories, but their names 

 are to have not validity in* formal taxonomy. 



Note. — The term variety is relegated to horticultural usage. 



Section II. Formation of Names. 



Canon 5. Specific and subspecific names consist of Latin or 



Latinized adjectives or substantives, the latter being either 



nominatives in apposition or genitives. 



Examples. — Hookerlanns ; europaeus ; vulgaris ; heterophyllus; 



malvlcola; Tnllplfera; Tuna ; Engelmanni; Sonorae ; Trifolll. 

 Canon 6. Generic and subgeneric names consist of Latin or 



Latinized substantives, or equivalent terms. 



Examples. — Rosa; Convolviilus ; Hedysarum ; Bartramia; 



Llquldambar ; Couronpita; Tsuga; Gloriosa ; Impatlens ; Manihot. 

 Canon 7. Names for subtribes, Orders, and intervening groups, 



are formed from names of component genera. 



a) For names of tribes add -eae, of families -aceae, of 

 Orders -ales, to the stem of the generic name. 



Examples. — Roseac ; Rosaceae ; Rosales. 



b) For names of subtribes add -anae, of subfamilies -atae, 

 of suborders -anes, to the stem of the generic name. 



Examples. — Rosanae ; Rosatae ; Rosanes. 

 Canon 8. Names for subclasses and higher groups consist of 

 plural Latin or Latinized substantives. 



Examples. — Monocotyledones ; Anglospermae ; Pteridophyta. 



Section III. Publication of Names. 



Canon 9. A specific or subspecific name is published when it 

 has been printed and distributed with a description (or in 



