HITCHCOCK AND CHASE—NORTH AMERICAN PANICUM. 5 
describing the species. In the absence of any indication that will 
point toward a particular specimen, the first one mentioned or the 
one from the locality first mentioned with the original description, 
or at least the first one among those equally eligible, is chosen as the 
type. 
Immediately following the citation of the name and its place of 
publication, is, quoted verbatim, when practicable, the “type 
locality,” or that portion of the author’s statement which indicates 
the origin of his specimen. Where there is doubt as to what specimen 
is the type, the reasons are given for choosing any particular specimen. 
All the types mentioned have been examined by one or both of the 
authors unless otherwise stated. After quoting from the original 
publication the portion relating to the type, we have indicated the 
location of the type specimen and have recorded any information 
concerning the specimen, or any data of significance upon the label. 
SYNONYMY. 
The name of each species accepted in this work is the earliest valid 
name, as governed by the recent American Code of Botanical Nomen- 
clature.* Under the accepted name the synonyms have been placed 
~ in chronological sequence. 
Nomina nuda have been mentioned only when they have found 
their way into botanical literature, especially the Index Kewensis. 
If such nomina nuda can be identified by type specimens they are 
placed as synonyms of the species to which the type belongs. If 
they were originally mentioned as synonyms but can not be identified, 
they are placed under those species to which they were assigned as 
synonyms. 
Typonyms are different names based upon the same type. When 
an author definitely changes a name, or substitutes one name for 
another, the old name and the new are typonyms of each other. This 
is the case even when the author making such change describes a 
different species, or cites incorrect synonyms or specimens that 
belong to a different species. As an example of a simple change of 
name we have,? “ Panicum ramisetum Scribn. nom. nov. Panicum 
subspicatum Vasey, U.S. Dept. Agr. Div. Bot. Bul. 8: 25, 1889, not 
Desvaux, Opuscules 84, 1831.” The evidence here is complete that 
Panicum ramisetum Scribn. and P. subspicatum Vasey are typonyms. 
As an example of change of name accompanied by a description of 
a different species may be given, Panicum polyneuron Steud.¢ The 
author had evidently seen no specimen of this himself, but translates 
2 Bull. Torrey Club 84: 167-178. 1907. 
6U.S. Dept. Agr. Div. Agrost. Cire. 27: 9. 1900. 
eSyn. Pl. Glum. 1:91. 1854. 
