may be niciitioncd as those containing our chief information: 

 The Species plantarum of Limucus (1758) of course forms the 

 ujroundwork; Walter, Plora Caroh'nia/ia (ITHJS); Michaux, Flora 

 Boreali-Ameriea7ia (1808); Pcisoon, Synopsis planturitDi ( ISO-")); 

 Pursh, Flora Septcntrionalis (KS14); Rafiiicsciuc, in various 

 scattered puhhcations (1815-40); Nuttall, Genera (1818), besides 

 much material published in Torrey and (Cray's Fl. X. Am.\ 

 DeCandollc, /'/v;(/';vw/As-, \'()1. \\ (1S8()); Hooker [W.].), Flora 

 Borcali' America ]ia (I888-4( I). 



The list of publications containing;- descriptions of new species 

 since Ton^ev and (irav's h''lora X. .\t)i. \'ol. I ( l.S8S-4()) is as 

 follows: 



Hooker a,nd Arnott: ISotanv Boeotiey Voya^'e (Is41). 



Hooker: London Joiir. Bot. vi. (1843). 



Buckley; Am. Jour. Sei. I. xlv. (1S43); Proc. Philad. Acad, i ls(;i i. 



Gray: PI. Fendlerian«> (1H48); PI. Wrightiana' (iK.'iO); PK Lindheimer- 

 ian«' (1850); Manual (185r)-(57); Proc. Amer. Acad, vi., vii. (18G8), viil. 

 (1870); Pacif. R. R. Rept. xli. (18(10); Ives' Report (I8(il); Am. Joui. Sci. 

 II. xxxiii. (18()2); Proc. Philad. Acad. (18(13). 



Torrey and Gray: Pacif. R. R. Rept. 11. (18.-)4). 



Torrey: Mex. Boundary Survey (1858). 



Chapman: Manual Southern States (18(10). 



Wood: Class-Book dscoi. 



Watson: Bot. King's Exped. (ls71);Am Natuialist, vii. (I,s7:it: Botany 

 of California (1876 and 1880); Proc. Aaier. Acad. xi. (187(1), xii. (ls77i, xiv. 

 (1S79), xvii. (1882), xviii. (1883). xx. (1885), xxi. (188(1). :,:xii. {1S,S7). 



Parry: American Naturalist, ix. (1875). 



Kellogg: Proc. Calif. Acad. i. (187(1). 



Curran: Bull. Calif. Acad. ill. 



Coulter Jc Rose: Bot. Gazette, xii. ( lss7). xiii. (18SS). 



Morong: Bull. Torrey Bot. Club, xiv. (lss7). 



Geographical distribution. — The order c( nt:iins about 10(1 

 genera and 1800 species, niostly distributed throughout temperate 

 regions and extending into the tropics along mountain systems. 

 Its most abundant represent;ition is in northern ICuropc and Asia. 

 'I'he genera are usu;dl\ widel\- distiibuted, while mcjst of the 

 species are quite restricted. North America, north of Mexico, 

 contains 59 genera and 288 species; of these, 7 are introduced 

 genera, leaving us Wl native genera, only 2'J of which arc strictly 

 North American; while of our species 217 are indigenous, anil but 

 18 of these are found at all in other countries. Of our native 



