59 



of this the region is a network of ranges and volcanic peaks where the 

 Tropical vegetation reaches 8000 feet altitude, and the peaks sometimes 

 reach the Lower Temperate, but rarely they extend higher to the Middle 

 Temperate, and only very rarely as on Orizaba, Popocatapetl, and Mt. 

 Colima do they reach the alpine. The lowlands about Colima and 

 Tampico southward have the dense vegetation and summer rains of 

 the humid Tropics. This is about as far as species of Astragalus extend 

 except a very few. The plateau floor from Arizona southward is 

 Tropical, i^ower California has a low range of mountains the entire 

 length but the flora rarely gets up out of the Tropical. San Pedro 

 Martir is an exception. 



The upper limits of the Tropical in the United States rarely 

 reaches 3000 feet altitude. In the Arizona region they are about 4000 

 feet, and rise as you go southward. 



The upper limits of the Lower Temperate life zone reach about 

 5000 feet in the Great Basin, but drop to about 1000 feet in the Colum- 

 bia Basin. In the south in Arizona they often reach 8000 feet altitude. 



Topographical details can be worked out on the map, and the 

 general zonal limits are best seen there. 



NOMENCLATURE. 



It has been my plan to make as few changes in names as possible. 

 The Vienna Code has been followed in the main and therefore the 

 oldest published name has been retained, except the meanin2:less 

 Astragalus astragalinus, for which I have substituted the A. andinus 

 of Nuttall. It is however my judgment that the Grayan method of 

 retaining the oldest name in the genus is better and productive of little 

 confusion, while the present method produces endless confusion. I 

 do not adopt the dictum "Once a synonym always a synonym," but I 

 have used the name of a species even if the same name has been used 

 for a species before that was a synonym of some earlier species, or 

 belonged to another genus. I have rejected Greene's substitutes for 

 Sheldon's hybrid names, for the reason that if we reject hybrid names 

 we shall have to go much farther back than Sheldon. 



I retain Astragalus for the reason that it is the earliest name and 

 the one generally accepted by the botanical World. The fact that 

 it is preceded in the Species Plantarum by Phaca should not require the 

 rejection of the genus, for the genus was proposed by Tournefort and 

 retained by Linnseus in his Systema before Phaca was created. 



Priority is the ony true basis for nomenclatural stability but no 

 one however zealous an adherent of this dictum accepts it without 

 the narrowest limitations. If we could ever know what was the true 

 priority in each case it would require the renaming of almost every 

 genus and species in the world as \ have already pointed out. This be- 

 ing out of the question the next thing is the general consent of botan- 

 ists. This has crystallized so that at the present time there is a general 

 assent to main points, which is that old names shall not be changed on 

 a technicality, and that in other respects 1753 shall be the beginning 

 date of nomenclature. The exceptions of the Vienna Code cover most 

 of the desirable reservations from the strict application of priority. 

 There should be certain other exceptions of genera. There should 

 be the abrogation of the rule about Latin descriptions, and the rejec- 

 tion of all genera proposed in early days that were not accompanied 

 by species. This will rule out the genera of Adanson, Necker, and 

 others, unless they were provided with species by others before any 

 other generic names were proposed for them. 



