GEOGRAPHIC DISTRIBUTION OF LIFE IN NORTH AMERICA. 373 
Central or middle division—This division extends from the eastern 
border of the great plains to the Sierra Nevada and Caseade Moun- 
tains. It was proposed by Agassiz in 1854, under the name “ Table- 
land fauna or fauna of the Rocky Mountains.” 
The extent to which it has been recognized will appear from the fol- 
lowing table: 
Date. Author. | Name given to region. | Based on— Rank. 
| 
1854 "Alrassiz...:......- | Mable-landefantnase se ee erate sate eae oe AMimals ees 3 
1859 | Le Conte -.....-... | Ciimmih (hein -<cpoceéobue - ionadneoSonceoosceese Insects's-2-- 22 1 
1863 | Binney (W.G.) -- _| Central PEOVINCOn == 0 .5s-c. ae  w s eeeescetee Mollusks -..-. 1 
1: (o(}a] 23) oe (EMiddileyprowinGee=nees cen. seccoss cece ~o8ibSe SiC Siac 1 
1866 | Grisebach ......-. PTOI O MOP Ones meet reer ae ecree eaeaaee ese eenG Rianise-— ee] 1 
TSO UOPOss2<occ~<- =< @enitralire sions: on -o2 sence sccecasaaeenescaccs oo Reptiles and 2 
| batrachians. 
TRG. Wallace ......\..- Rocky Mountain sub-repion.............-.--....- Animals -...-- 2 
ISTE AMON oe <<. oa 35 MMe pro Van COlsae sey eee ic yaaa cee bar COs. soeisetes 2 
ORR PGR a crete ow clown e, =~ Contralprovince>= cc sas<s<-ssacecs seseaas ene - Plants\eeesa 1 
TARGa WE ACK ANC. ..<.-2s0. | Rt COR ee eee eens eae te doe A aay ewe 2. | Animals ...... 1 
ISRS | eONOaN-..-~.------ @entralitegione. on. -soeeie on coe eiawesee See cee Mollusks ..--. 3 
1884 10 Th Re See Se eeaae leMoni ann cistron. s-Seto. 8 seer ae oe (Plenits:sso-- ae 2 
1886 | Hartlaub ....-..-... | Rocky Mountain region ..............-..--------- Birds assess. 2 
LOST ei prinis = -<-.--¢ Rocky Mountain sub-rerion: =... - 2-2 - == een ee Animals ....-. 2 
ESOT ErONOGL os. -.2 225. Prairie tora a. 22 cian sae os anelsion seine deicceeenes cee ‘Plants see 1 
1889 | Ridgway..-....--. | Rocky Mountain or middle district .--......-.---. BITES yas a= 2 
| 
Pacifie or California division.—This name has been very generally 
applied to the Pacific coast region of the United States. It was first 
recognized by the botanist De Candolle in 1820. Pickering, in 1830, 
named it the Californian flora, but knowing little or nothing of the 
Sierra Nevada, and believing the Rocky Mountains to be the only moun- 
tain system of importance in North America, extended its eastern 
boundary to that range. In this way he was followed by the botanist 
Hinds, in 1845; by the conchologists, Amos Binney, in 1851, and Wood- 
ward, in 1856. Agassiz, in 1854, was first to fix its eastern limit at the 
Sierra Nevada and Cascade mountains, where it has been permitted to 
rest. Its north and south boundaries have undergone considerable 
fluctuations. 
