HARD WICKE ' S S CJENCE- G O SSI P. 



59 



complexity of structure adapted to more perfect 

 exercise of function : and because it is in some cases 

 difficult to judge organisms correctly by this standard, 

 that is surely no reason for giving up the word when 

 there can be no doubt as to what it indicates. The 

 Campanulas, again, though regular as to the shape of 

 their flowers, may well be considered an advanced 

 type, taking into account the adaptation of the bell- 

 like form to the visits of humble-bees, the honey 

 protected from many insects, the well-marked pro- 

 terandry and subordinate contrivance for cross-fer- 

 tilisation : the same may in part be said of the Scillas, 

 As to the position of the Veronicas among the Scro- 

 phulariacccc, a few words of Midler's throw^ some 

 light on the question : " In spite of its apparently 

 simple flower, Veronica is by no means a primitive 

 genus among the Scroiohularinece ; the symmetrical 

 flower, the specially differentiated nectary, the reduc- 

 tion of the sepals and petals to four, and of the 

 stamens to two, are all characters widely removed 

 from the primitive type. The short-tubed species of 

 Veronica must be looked upon as the more primitive, 

 from which the long-tubed type of V, spicata has been 

 evolved by the agency of bees and sand-wasps." The 

 yellow iris is, I take it, a special case not yet under- 

 stood ; similar cases are ably discussed in the chapter 

 on " Retrogression " in Mr. Grant Allen's " Colours of 

 Flowers." From this I will quote the " hypothetical 

 explanation " of the colours of the Ligulata;, Mr. Bul- 

 man's last instance : " The primitive ancestral composite 

 had reached the stage of blue or purple flowers while 

 it was still at a level of development corresponding to 

 that of the Scabious or the Jasione. The universality 

 of such colours among the closely allied Dipsaceae, 

 Valerianeae, Lobeliacese and Campanulacese, adds 

 strength to this supposition. The central and most 

 primitive group of Composites, the Cynaroids, has 

 kept up the original colouration to the present day ; 

 it includes most of the largest forms, such as the 

 artichoke, and it depends most of any for fertilisation 

 upon the higher insects. Very few of its members 

 have very small florets. All our British species 

 (except the degenerate Carlina) are purple, sometimes 

 reverting to pale pink or white, while Centaiirea 

 Cyaniis, our most advanced representative of the 

 tribe, rises even to bright blue. 



Next to the Cynaroids in order of development 

 come the Corymbifers, some of which have begun to 

 develope outer ligulate rays. Here the least evolved 

 type, Eupatorium, with few and relatively large 

 florets, is usually purple or white, never yellow. But 

 as the florets grew smaller, and began to bid for the 

 favour of many miscellaneous small insects, reversion 

 to yellow became general. . . . The Ligulates were 

 again developed from yellow-rayed Corymbifers by 

 the conversion of all the disk florets into rays. Ap- 

 pealing for the most part to very large and varied 

 classes of miscellaneous insects, they have usually 

 kept their yellow colour ; but in a few cases a fresh 



progressive development has been set up, producing 

 the violet -blue or purple florets of the salsify 

 [Tragopogon porrifolius), the deep blue Sonchus 

 Alpinus, and the bright mauve succory, Cichorium 

 Intybiis." 



Mr. Bulman says that he is not at all satisfied that 

 M tiller intends in the words quoted by me about the 

 appearance of red, violet and blue in flowers to assert 

 that the most advanced flowers are usually of these 

 colours. As Midler does not categorically state this, 

 it is rather difficult, in the face of Mr. Bulraan's 

 warning about the use of the word "advanced," to 

 show it. The general conception of the meaning of 

 the word is, however, I believe, what I have in- 

 dicated above ; and there is no doubt that generally 

 speaking " flowers whose honey is quite concealed 

 and which are visited by more or less long-tongued 

 insects " have undergone various and extensive 

 adaptations of structure which fit them for, the more 

 perfect discharge of the function of fertilisation by 

 means of these insects. The blue colour in Hepatica 

 and Verbasctim is to be explained as developed by 

 the SyrphidiE, to which the flowers are adapted 

 and which admire bright colours, being themselves 

 brightly adorned, as the result of sexual selection. 

 (Mlille'r). 



It is certainly rather startling to be told that a 

 statement of Midler's in his " Befruchtung," " com- 

 pletely annihilates the whole Darwinian theory of the 

 development of flowers by the selective agency of 

 insects," when we consider that Miiller seeks all 

 through the book in question to explain the whole 

 of the structures met with in flowers as the result of 

 natural selection acting through insect agency. The 

 fact is that Mr. Bulman has, not exactly misquoted, 

 but given the wrong context to Miiller's statement, 

 which really runs : "that in general antJiophilous 

 insects are not r(7«yf«^^ by hereditary instinct to certain 

 flowers, &c." (the italics are my own) ; while Mr. 

 Bulman's version of it is " bees are not confined,' '&c., 

 which is a very different matter. Keeping the italicised 

 words in mind, we see that Mr. Bulman's argument 

 about the " complete annihilation " of the Darwinian 

 theory falls to pieces ; for the phrase " anthophilous 

 insects in general" is not synonymous with "bees," 

 and to say that they are not " confined " to certain 

 flowers by hereditary instinct is not at all the same 

 thing as to say that they have no hereditary pre- 

 ference for certain flowers ; yet this is the conclusion 

 which Mr. Bulman has drawn. To enforce this 

 obvious difference we have only to read another 

 statement of Midler's: "The most specialised, and 

 especially the gregarious bees have produced great 

 diff'erentiations in colour, which enable them, on their 

 journeys, to keep to a single species of flower." 

 I am afraid, therefore, that I cannot agree with 

 Mr. Bulman that Miiller's conclusions on this point 

 would have been more in place in his paper than in 

 mine. 



