THE FLORA OF PERTHSHIRE. 323 



in the farm of Newmill in a field of barley." Siibularia is quoted 

 from the Linnean Society's Herbarium as found in the Loch of 

 Gluny by Brown ; McRitchie has the following note in Herb. Mus. 

 Brit.: "24 Sept. 1793. Mr. Brown on his arrival here in the 

 beginning of August detected two plants of it near the E. shore of 

 the loch of Clunie. I have since found it in abundance on the W. 

 side near the Castle hill in about 5 feet water." There is little 

 doubt that a careful search in the Herbarium would reveal further 

 contributions from these early collectors, as well as other matters 

 of interest — such, for instance, as Don's original specimens of 

 Veronica saxatilis from Ben Lawers and Meall Ghaordie, from which 

 the figure in English Botany was drawn. 



The interesting notes under Arabis ijetrcBa show the careful 

 observation which Dr. AVhite bestowed upon the critical species 

 which came under his notice, and also the judicious modesty which 

 led him to refrain from bestowing a name upon every form which 

 presented points of distinction. This indeed is noticeable through- 

 out the book ; forms which by some authors would, on far slighter 

 grounds, at once be printed with a new name, are observed ; a note 

 upon them, sufficient to attract the attention of later observers, is 

 placed on record ; and there the matter is left. If this plan were 

 always followed, nomenclature would be less copious and less puzzling 

 than it is at present. This Perthshire form of A . petraa, for example, 

 has received no fewer than three names from one botanist, not one 

 of which can stand, even if the plant should in the future be 

 regarded as specifically distinct, as it has been in the past. Mr. 

 Druce in the Exchange Club Report for 1892 first named it 

 as A. 2)etra;a var. grandifolia, and then claimed for it specific 

 distinctness : it " may be described as distinct as grandifolia ; 

 should there already be a plant so named, I would suggest the 

 name of A. scotica." If this principle of naming were generally 

 followed, there would be no limit to the number of names that 

 might be "suggested." In this instance, however, Mr. Arthur 

 Bennett (Journ. Bot. 1894, 114) promptly identified the plant with 

 one described as A. ambigua by DeCandolle (Syst. ii. 231) in 1819, 

 and referred to A. petrcBa as a variety (var. ambigua) by Fries in his 

 third Mantissa (1842). 



A similar unwillingness to maintain names for mere forms may 

 be noted under Castalia speciosa, where Dr. White says : "Flowers 

 variable in size and stigma rays in number, without a relative 

 correspondence. Hence there seems to be no valid reason for 

 separating the small-flowered form as a variety. Plants inhabiting 

 the highland lochs have usually the smallest flowers; large-flowered 

 plants in lowland ponds have generally been introduced." He 

 inclines, however, to consider that Barbarea arcuata Eeich. "de- 

 serves at least sub-specific rank"; as to B. vulgaris he is "far from 

 convinced" that it "is anything more than an introduced plant 

 with us, or at the best a weed of cultivation." In some cases Dr. 

 White is disposed to think plants which have been regarded as 

 introductions may have claims to nativity ; thus he says of 

 Cheiranthus : " so abundant on the precipices of several of our trap 



