62 



NOTICES OF BOOKS. 



Trifolium repens, L. 

 Poteatilla auseriua, L. 

 Callitriche verua, L. 

 Ilippuris vulgaris, Z. 

 Myriopliyllum verticilla- 



tura, Z. 

 Portulaca oleracea, J. 



„ var. sylvestris, 



Montia fontana, L, 

 Daucus Carota, L. 

 Galium Aparine, Z. 

 Ageratum conyzoi<Ies, L, 

 Erigeron Canadeuse, L. 

 Eclipta erecta, Z. 

 Maruta Cotalaj Z. 

 Artemisia vulgaris, Z. 

 Gnaplialiumluteo-album, Z. 



Prunella vulgaris, Z. Alo 



ilarrubium vulgare, Z. 



Lamium amplexicaule, Z. Phleum pratense, Z. 



lecurus geniculatus, 

 „ pratensia, Z. 



Plantago major, Z. 



Panicum Crus-galli, Z. 



n 



lanceolatus, Z, Setaria glauca, Beauv. 



Cheaopodium murale, Z. 



album, Z. 



39 



» 



» 



>» 



viridis, Beauv. 

 Italics, Kunth* 



aml)rosioide3,Z. Phragmites communis, Trhu 



Amaranthus Blitum, Z, Cynodon Dactylon, Fers. 



y 



Polygonum aviculare, Z. 



>» 



3> 



Couvolvulus, Z 

 ampliibium, Z. 



Poa Eragrostis, Z. 

 „ annua, Z. 



Ilumex Acetosella, Z. 

 TJrtica urens, Z. 

 J, dioica, Z. 

 Lemna ininor, Z. 



>> 



)) 



trivialis, Z, 

 nemoralis, Z. 



» 



„ trisulca, Z, 

 uliginosum, Z. Tryplia latifolia, Z. 



Glyceria aquatica, Sm^ 

 „ fluitans, 5r. . 

 Catabrosa aquatica, Beauv, 

 Briza minor, Z. 

 Dactylis glomeraia, Z. 



Senecio vulgaris, Z. 



93 



angustifolia, Z. Triticum repens, Z. 



Taraxacum Deus-leonis. Zannichellia palustris, Z. Ti-isetumsubspicatumj^^^Mr. 

 Sonclius oleraceus, a& p,L, 



■ L 



The conclusions drawn from the study of this list are stated to be 

 very striking, and strongly confirmatory of the general laws laid down 

 in the preceding articles ^ they are 



1. No species of Phsenogamic plants extends over the whole surface 

 of the globe ; one alone, the Sonchus oleraceus^ can perhaps exist in all 

 climates, from pole to pole, but demands a cultivated soil or azotized 



humus. 



2.. The number of species known to occupy one-half of the globe's 

 surface is very small, and confined to 18 species. 



3. The total number occupying one-third of the surface of the globe 



is 117 ; and supposing that future researches increase it to 200, it will 



still form an extremely small portion of the whole Pheenogamic vegeta- 

 tion* (about 0001), ■ 



♦ That this number is capable of far greater increase than M. de Candolle sup- 

 poses, we have no doubt. The progress of modem discovery is to reduce apparent 

 species, which are founded upon characters that are pectdiar ouly to the individual, 

 or fragments of an individual, preserved in our collections. The mass of described 

 species are in this catep:ory, so that the list in question will be increased — 1, by the 

 discovery of well-established species in countries they are not now known to inhabit ; 

 and, 2, by the union of supposed distinct species : and the numerator of the fraction 

 expressing their proportion to the whole Phjcuogamic vegetation will be increased 



