Bibliographical Notices. 135 



very local plants are australs and arctics, with some very few others, 

 scattered elsewhere" (p. 445). 



" The number of species common to Great Britain and to counti'ies 

 more southward is greater than the number of those common to 

 Britain and countries more northward. The floral resemblance, 

 however, is greater with the northern countries, because these latter 

 commingle with them a less number of non-British species" (p. 387). 



" Regarding the British Isles collectively, the most distinctive 

 peculiarities in their flora are found on the toestern side.'' The Irish 

 Spiranthes gemmipara is the only plant cited as absolutely restricted 

 to our islands. Again, it is in the west that occur the Saxifrages and 

 Heaths, so characteristic of the Irish Highlands, as well ?cs. Erioecmlon 

 septangulare, the sole representative in Europe of its order and genus, 

 and, on this side of the Atlantic, found in Ireland and Scotland only. A 

 few other species are quoted as mentioned only in the British Floras, 

 but with the caution that they are too little known, or too closely 

 related to other species, to be considered more than local races ; yet, 

 even as such, their existence is considered by our author important 

 evidence of a " local inchoation." But more weight is probably to 

 be attached to the position and abundance of plants characteristically 

 prevalent in, though not pcciliar to, Britain. It is not a little re- 

 markable, as bearing upon the theory of progressive development, 

 that so few varieties even have hitherto been found restricted to the 

 British Isles. Had both been developed from the same pre-existing 

 form, it would hardly have been expected that, when occurring under 

 circumstances so different, the British species and varieties should be 

 found to correspond so closely with their continental representatives. 

 It is true, the British varieties are often less marked, as might be 

 expected, under the less varied conditions offered by a narrower range 

 of soil and by a more equable climate. 



The plants enumerated by Mr. Watson as perhaps peculiar to 

 Britain may be summed up as follows : — Dry as depressa (Bab,), too 

 closely related to D. octopetala. Helianthemum Bi-eweri (Flanch.), 

 probably a state of H. ffuttatum. Geranium lancastriense (With.), 

 which preserves its characters when grown in a garden, though it is 

 not stated whether its distinctness from G. sanguineum has been 

 tested by sowing. Sedum Forsteriamim (Smith), whose aspect is ad- 

 mitted to be distinctive, though its characters are ill-defined ; but the 

 genus is so little known, that our plant may yet be identified with 

 some continental species or variety. Allium Babingtonii (Borr,), 

 perhaps a variety of ^, Amj^eloprasxim, and not certainly indigenous in 

 the British stations, Viola Curtisii (Forst.), which, under cultivation, 

 approaches V. tricolor, and has lately been identified with V. sahulosa 

 of Boreau, a plant of Belgium and the north-west of France. Last 

 comes Saxlfragu Andreicsii (Harv.), now believed to be a garden 

 hybrid. There are, besides, a few Ilieracia, llubi, Rosce, and Salices 

 described by British authors only ; but these genera are as yet too 

 imperfectly understood to be reckoned in the estimate, 



As to the presumed relationship between the British and North 

 American floras, shown by the presence of Eriocaidon septangulare^ 



