320 Bibliographical Notices. 



must, for the same reason, be rejected from almost every other one," 

 an argument, by the way, which has been employed to account 

 for our ignorance of the original "specific centres" "of the cereals 

 themselves. 



Great stress is laid upon judging of the claims of plants to be 

 regarded as natives from the knowledge of their whole "area" 

 or general distribution, much in the same way as recommended by 

 Alphonse DeCandolle ; but those who have perused the fourth volume 

 of Mr. Watson's ' Cybele ' are aware how much there is to be said 

 upon the other side about the high importance to be attached to the 

 " nature of the station" and to the circumstances under which the 

 suspected plant occurs. As often remarked, allowance must also 

 be made for the extreme rarity of some species that are probably 

 natives, though with us at the outskirts of their range, or become 

 very much rarer than was formerly the case by the cultivation and 

 drainage of land. 



The * Handbook ' is no mere compilation, for its author tells us 

 he has conscientiously re-examined his plants, and compared them 

 with Continental specimens of the same species. 



We have some misgivings whether the tyro is likely to acquire a 

 just appreciation of the value or limits of a species when he is taught 

 to include under one name no less than five plants (as in the case of 

 Cerastium vulgatum), which amounts to little more than recognizing 

 a subsection or subgenus. We suspect that the beginner's belief in 

 the existence of a species at all will be not a little shaken when he 

 gathers, growing side by side, two plants so different as Cerastium 

 glomeratum and C. semidecandrum, and yet is told they are identical. 

 Nevertheless, no proof has been adduced from cultivation ; no inter- 

 mediates occur among hundreds of both kinds ; and at the same 

 time nearly all systematic botanists are agreed to believe that a 

 species has limits somewhere, though we may not yet have found 

 them. The conflicting opinions on this subject, even within the 

 bounds of a Flora so small as that of Britain, sufficiently show that 

 it is not in books we must look for these limits. 



We have space for only a few instances of Mr. Bentham's sweeping 

 combinations, for most of which no reason is given, except the opinion 

 of the author, or the authority of some eminent, but often ancient, 

 writer. 



We much regret this omission, as it can hardly be expected that 

 the "Liberal" or "Progress" party, far less the "Radicals," will 

 submit to such despotic assumptions without ample proof. 



There is but one Arctium. Ah, lucky tyro ! how we envy him a 

 load of difficulties removed at one stroke of the pen ! 



The Ranunculi, of the Batrachium section, are all swamped under 

 one species ; but if we have our old friend R. aquatilis restored to 

 its ancient dignity, it must feel somewhat alarmed at finding itself at 

 the head of a larger family than it ever acknowledged before. 



Similar amalgamations will be found under Potamoyeton pusillus y 

 which now includes a whole section of narrow-leaved species. 



Potamoffeton natans is joined to P. oblonyus, and also to P. plan" 



