228 JOURNAL OF THE WASHINGTON ACADEMY OF SCIENCES VOL. 11, NO. 10 



II. Major Temperate Zone.— South and north of and below Major 

 I with Minor Temperate 1, 2, 3, 4, 5, 6, and 7. South and north of 

 and below Minor Frigid 4. 



III. Major Tropical Zone.— South and north of and below Major 

 II, with Minor Tropical 1, 2, 3, and 4. South and north of and below 

 Minor Temperate 7. 



This suggested system of designations and classification of the zones 

 is put forward with the idea of replacing names based on geographical 

 features or political divisions of one country, continent, or hemi- 

 sphere with designations that would be applicable to any continental 

 or insular area of both hemispheres. 



The Minor Temperate 1 to 7, Minor Frigid 4 and Minor Tropical 

 1, are wholly, or in part, equivalent to the Merriam life zones as 

 related to North America. Thus: 



Minor Frigid 4 = Merriam's Boreal or Arctic- Alpine. 



Minor Temperate 1 = Hudsonian; 2 = Canadian; 3 = Transition; 

 4 = Upper Austral and Upper Sonoran in part ; 5 = Lower section of 

 Upper Austral, Sonoran and Carolinean and upper section of Lower 

 Austral, Lower Sonoran and Austroriparian, and represents a transi- 

 tion between 4 and 6; 6 = Lower Austral and Sonoran in part; and 

 7 = Gulf strip as a transition between Minor Temperate 6 and Minor 

 Tropical 1 which latter = Merriam's Tropical. 



The range and limits of the minor zones are characterized pri- 

 marily by certain average ranges of temperature and, as related to world 

 distribution, may be designated as terrestrial thermal zones. 

 Each Minor Zone may embrace in its world-wide range many types 

 of climate and life peculiar to certain regions, local areas and places. 

 Therefore, while their numerical designations and relations are main- 

 tained throughout, each minor is subject to division into many recog- 

 nizable sections and subsections; each characterized by some peculiar 

 regional or local conditions as to life, climate, weather, and physical 

 adaptation of the land to various types and associations of life. 



In general the position occupied by a given place may represent 

 the upper, middle, or lower section of a zone designated as follows: 

 ( — ) lower, ( — .) lower middle, (.) middle, ( + •) upper middle, ( + ) 



upper; and ( h) the lower of one and upper section of another or 



the colimits of two zones, as ( — 3 -f 4) = lower 3, upper 4. 



The index or characterization elements of the minor zones and their 

 subdivisions into sections are many and varied. Some of the prin- 

 cipal ones are the thermal index; life type and ecological index; the 



