Aug. 1, 1868.] 



HARDWICKE'S SCIENCE-GOSSIP. 



171 



examples as they occur to us, and even now leaving 

 some of the present order, as the two species of 

 Delph iniicm, unnoticed. 



The long smooth-headed Poppy {Papaver ditbium 

 of older authors) has lately been shown to be com- 

 posed of two distinct forms, which may be readily 

 recognized by a very simple test. The first, which 

 is called by some P. Lamottei, but usually retains 

 the name of P. dubiiim, has the sap milk-white, not 

 turning yellow on exposure to the air ; while in the 

 second, P. Lecoqii, the sap becomes dark-yellow 

 when similarly treated. Erom a note in Gibson's 

 "Elora of Essex," a work in which much useful 

 information upon critical species will be found, it 

 appears that the capsules of P. Lecoqii are " long, 

 club-shaped, suddenly narrowing near the base ;" in 

 P. Lamottei they are shorter, narrowing gradually 

 to the base." Mr. Gibson says that although " the 

 differences between them are slight," they are 

 " apparently constant both in cultivation and in 

 their natural localities," and that the two plants 

 often grow intermixed. Professor Babington, in 

 his " Elora of Cambridgeshire," first described 

 and distinguished the two forms as occurring in 

 England. 



Of the order Crucifera, which furnishes us with 

 many " splits," we will take one common and gene- 

 rally distributed plant, the Hairy Bitter Cress 

 (Cardamine hirsuta). The usual form of this is a 

 small annual, with slender, nearly straight stem, 

 and small white flowers having four stamens. This 

 grows usually in dry but sometimes in damp places, 

 and is by no means unfrequent as a weed in gardens. 

 The other form, C. sylvatica, is a larger plant, with 

 stouter, wavy, and more leafy stem, and six- 

 stamened flowers. This is said by Professor 

 Babington to be " common, especially in woody 

 places ;" we have, however, more usually found it 

 by the sides of streams, where its more luxuriant 

 appearance at once attracts notice. In this, as in 

 several of our " splits," there is a general difference 

 from the normal form, very apparent to those who 

 are acquainted with both, but impossible to define 

 accurately on paper ; and in this way, although the 

 distinctions set down may appear slight, their 

 importance is greatly enhanced to those who will 

 examine specimens for themselves. Babington 

 classes C. sylvatica as an annual species ; in 

 " English Botany " it is said to be biennial or 

 perennial. 



Passing on to the Violets (T'iolacea), we must 

 devote a short space to the Wood Violet {Viola 

 sylvatica), itself, by the way, not very long clearly 

 separated from V. canina. This is divided into two 

 forms, which Babington says are probably distinct 

 species. The first of these, V. Reichenbachiana, is 

 the rarer of the two, although " it has been found 

 sparingly in most of the districts in which it has 

 been searched for." We have this year found it in 



Buckinghamshire, after some years' searching ; but 

 we must say that the descriptions given in both 

 our works of reference strike us as scarcely as clear 

 as is desirable. Mr. Watson's note in the "Elora 

 of Surrey " best conveys the peculiar features of 

 V. Reichenbachiana ; he says it is " readily distin- 

 guished by its narrower petals of pale purple (fig. 170), 

 with a deeper spot at their base, and more flattened, 

 always purple, spur." These particulars exactly 

 characterize this form ; in addition to which, the 

 veins of the lowest petal of V. Reichenbachiana are 

 few, and but slightly branched, while in V. Riviniana 

 they are numerous, and much branched. V. Rivi- 

 niana is a larger and handsomer plant (fig. 171), 

 with broader and richer flowers : these differ in colour 

 from those of V. Reichenbachiana, but not more in 

 reality, one would suppose, than in the estimation 

 of different observers. V. Riviniana has, according 

 to Mr. Syme, " pale bluish-purple " petals ; but 

 Professor Babington considers them " blue " ; while 

 those of V. Reichenbachiana are " pale reddish- 

 purple," according to the former, and " lilac " 

 according to the latter ! Both forms grow inter- 

 mixed in the neighbourhood of Wycombe, and both 

 occasionally vary with white flowers ; but V, Reichen- 

 bachiana is here by far the less frequent of the 

 two, as it also is in the neighbourhood of Denham, 

 Bucks, whence we have received specimens. The 

 figure of V. Reichenbachiana in " English Botany " 

 strikes us as scarcely satisfactory ; the colouring of 

 the petals is not quite correct, and their narrowness 

 is more conspicuous in the plate than in the living 

 specimens which we have examined. Mr. Bentham 

 unites all the forms of V. sylvatica and V. canina 

 under the name of the latter species. The Pansy of 

 our cornfields is by some divided into two forms : 

 the first, the true V. tricolor, with yellow and white 

 petals, more or less shaded with blue, which much 

 exceed the spreading sepals : the second, V. arvensis, 

 with yellow-white petals, without any tinge of blue, 

 which occasionally equal, but never exceed, the 

 erect sepals. Extreme forms, such as those figured 

 in " English Botany," are readily referable to each 

 of these ; but intermediate states may frequently be 

 found. Our common cornfield Pansy in the Wycombe 

 district is probably to be referred to V. tricolor, as 

 it has the large petals and spreading sepals charac- 

 teristic of that form ; but the blossoms rarely have 

 even a trace of blue in them, and specimens ap- 

 proaching to the figure in " English Botany " are 

 very rare. We suspect this is the form referred to 

 V. arvensis by Mr. Watson in the " Elora of 

 Surrey." The two are scarcely distinguishable. 

 The figure of V. arvensis in "English Botany" is 

 remarkably good. 



The Milkwort which grows among the grass on 

 commons and heaths differs considerably from the 

 large and handsome form which spreads in masses 

 about chalky banks and wood-sides. The former, 



h 2 



