BFNTHAM ON THE SPECIES AND GENERA OF PLANTS. 1 39 



whole of that range certain distinctive characters, of no great impor- 

 tance in their respective genera, yet apparently constant in that parti- 

 cular case. Such are, for instance, Viola odorata and hirta, Lychnis 

 vespertina and diurna, Ulex JSuropaeus and nanus, Sonchus oleraceus and 

 asper, Senecio jacobcea and eruccefolius, Orchis maculata and latifolia, 

 Juncus articulatus and obtusiflorus, and a number of others. In some 

 of these cases, the balance of evidence has appeared to me to be in fa- 

 vour of their specific distinctness, in others of their identity, and I have 

 so recorded them in my Hand-book, but often with great hesitation ; 

 and it is not improbable that further observation and experiment may 

 induce a change of opinion in regard to some of them. 



Again, there are sometimes two, three, or more forms, having eveiy 

 appearance of really distinct species, all common over an extensive area, 

 or spreading into distant regions, and everywhere retaining their cha- 

 racters ; and yet we are occasionally startled by the appearance of inter- 

 mediate forms of various degrees, suggesting in some minds the specific 

 identity of the whole series, in others a progressive development from 

 one species to another ; and in others, again, natural hybrids ; whilst in 

 some instances the observer may have been deceived by accidentally ab- 

 normal specimens, carefully preserved and occupying a conspicuous part 

 in the herbarium, without any record of the attending circumstances 

 which might have accounted for their production, but which forms in na- 

 ture are very rare, and of mere temporary existence. Such occur, for in- 

 stance, among some of the common species of Rumex, Mentha, &c. It 

 is also frequently a matter of great nicety to determine what constitutes 

 an intermediate form ; for two plants, to be really intermediate, should 

 not be so in one character only,, but in general habit and aspect, in a 

 combination of all the characters which separate the two species it 

 stands between. The species of Carduus (including Cirsium) for instance, 

 have been artificially divided into species, with their leaves decurrent or 

 not. "When, therefore, a specimen of one which has usually sessile leaves is 

 met with having them slightly decurrent, it has been, on that account 

 alone, set down as intermediate between that and some other species to 

 which it shows no approach in any other point ; and thus figures in 

 books as a hybrid, or a distinct species, according to the tendency of its 

 describer. 



One source of deception as to the real permanency of an abnormal 

 form, even when observed without variation in a wild state in the 

 greatest abundance, arises from the facility with which certain peren- 

 nials, or shrubs, multiply by runners, suckers, bulbs, or other modes of 

 division, especially in cool, moist, and comparatively sunless climates 

 like our own. Individual peculiarities are thus propagated naturally 

 in a wild state, as we do artificially in gardens, spreading over the 

 country in such numbers, as to be mistaken by the cursory observer for 

 races, if not for species. Seedling brambles, mints, creeping-rooted 

 weeds, &c, are rare in our climate ; the bulbiferous Alliums, the vivi- 

 parous grasses, many introduced plants, such as the Perhvinldes, Hype- 

 ricum grandifiorum, &c, seldom produce any seed. Carduus arvensis 



