AUSTRAL-AMERICAN REGIONS. 



81 



G-naphalium (No. 38). On tlie tract of sand-hillocks. 



(No. 39) ; the calyx or involucre contracted above (connivent). On the tract of 



sand-hillocks. 



(No. 40); the flowers in capit., aggregated. 



Senecio? (No. 18); abnormal. Iloary, the leaves simple. 

 (No. 19). Green ; the leaves succulent. 



(Leptocarpha rivularis ? No. 1 ; compare also Flourensia corymbosa) ; resembling Califor- 

 nia plant of Nutt. Gaillardia-like ; the receptacle paleaceous ; akenium bicaudate, or 

 having two membranous awns. On the tract of sand-hillocks. 



Gen. Coreopsis-like (No. 1); the inner involucre monophyllous ; no floret rays. 



■ (No. 2); a second species?. Glaucous; the inner involucre monophyllous. 



Ambrosia (No. 7). On the tract of sand-hillocks. 



Samolus (compare Brazil, and No. 1 United States). On the river-bank, within reach of 

 the infilti'ation. 



Asclepias (No. 14). Normal, and large-leaved; as though unaffected by the drought. 

 Growing on the Upland plain. 



Gilia? (No. 1). Annual, small. Cantua-like ; the leaves dissected ; the calyx awned. 



Cressa (compare Peru, No. 1 Hawaiian Islands, and No. 3 California). The flowers pale- 

 pink; styles two. 



Heliotropium Curassavicum ? (compare Hawaiian Islands, and No. 8 Interior Oregon, 

 North California, and the sea-coast of Maryland). Growing in the drifting sands of 

 the sea-shore. 



Solanum (No. 53 ; perhaps a congener of our Arkansas Nycterium) ; the stamens unequal ; 



the style declinate, incurved. 

 Lycium ? (No. 5) ; compare also Solanum lycioides. A spiny shrub ; the stems and 



branches white ; the leaves small. 



? (No. 6) ; perhaps a second species ; pubescent and coarser. 



Limosella tenuifolia ? (compare No. 1 United States). On the muddy shores of the river. 



Most of the specimens lost. 

 Capraria-like (No. 1). Annual. Having the habit of the above-mentioned Gilia; but 



the capsule two-celled. 



Gerardia (No. 8). Habit of Gratiola. Growing along the river-bank, within reach of 

 the infiltration. 



Gen. Labiat. (No. 1). The odor Thymus-like. An unsightly shrub; the leaves being 

 reduced to mere green granules, oppositely-disposed along the coarse blackish branches. 

 On the Upland plain, and elsewhere. 



Verbena "pulchella?" (No. 11). The leaves dissected; the flowers small. 



Zapania (compare No. 1 North California). Small. 



Xanthium strumarium ? (compare Hawaiian Islands, our Atlantic States, and No. 1 

 Egypt). Growing spontaneously, but probably introduced. 



• spinosum, (No. 3). Only one stock met with; and this was growing in a situa- 

 tion that indicated the bringing of the original seed in some vessel ; possibly, all the 

 way from our Middle States. 



Polygonum avicularc ? (compare No. 10 Western Oregon, Interior Oregon, and our At- 

 lantic States). Growing spontaneously, but probably introduced. 



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