198 HORTICULTURIST'S RULE-BOOK. 



ART. 15. Each natural group of plants can bear in science 

 but one valid designation, namely, the most ancient, whether 

 adopted or given by Linnseus, or since Linnaeus, provided it be 

 consistent with the essential rules of nomenclature. [The ex- 

 act work of Linnseus from which names may start is not desig- 

 nated.] 



ART. 31. All species, even those that singly constitute a 

 genus, are designated by the name of the genus to which they 

 belong, followed by a name termed specific, more commonly of 

 the adjective kind. 



ART. 35. No two species of the same genus can bear the same 

 specific name, but the same specific name may be given in 

 several genera. 



ART. 37. Hybrids whose origin has been experimentally dem- 

 onstrated are designated by the generic name, to which is 

 added a combination of the specific names of the two species 

 from which they are derived, the name of the species that 

 has supplied the pollen being placed first with final i or 

 o, and that of the species that has supplied the ovulum com- 

 ing next with a hyphen between (Amaryllis vittato-regince, 

 for the Amaryllis proceeding from A. regince fertilized by A. 

 vittata. 



Hybrids of doubtful origin are named in the same manner as 

 species. They are distinguished by the absence of a number (in 

 descriptive works), and by the sign x being prefixed to the 

 generic name (x Salix capreola, Kern). 



ART. 38. Names of sub-species and varieties are formed in 

 the same way as specific names, and are added to them accord- 

 ing to relative value, beginning by those of the highest rank. 

 Half-breeds (mules of florists) of doubtful origin are named 

 and ranked in the same manner. 



Sub-varieties, variations, and sub-variations of uncultivated 

 plants may receive names analogous to the foregoing, or merely 

 numbers or letters, for facilitating their arrangement. 



ART. 39. Half-breeds (mules of florists) of undoubted origin 

 are designated by a combination of the two names of the 

 sub-species, varieties, sub-varieties, etc., that have given birth 



