3 2 4 



NATURE 



[August 3, 1882 



ample. Its flowers are usually blue or white, and the 

 greater number of them, like the harebell {Campanula 

 rotundifolia) and the Canterbury bell {C. media), are deep 

 blue (Fig. 15). We have nine British species of the genus, 

 varying from pale sky-blue to ultramarine and purplish 

 cobalt, with an occasional relapse to white. Rampion and 

 sheep's bit, also blue, are clustered heads of similar 

 blossoms. The little blue lobelia of our borders, which is 

 bilateral as well as tubular, belongs to a closely-related 

 tribe. One of our British species, Lobelia Dortmanna, 



\/ 



ype of simple open AU, 



is sky-blue; the other, /.. urens, is a dingy purple. Not 

 far from them are the Dipsaccic, including the lilac sca- 

 bious, the blue devil's bit, and the mauve teasel. Amongst 

 all these very highly-evolved groups blue distinctly forms 

 the prevalent colour. 



In the great family of the Ericaceec, or heaths, which is 

 highly adapted to insect fertilisation, more particularly 

 by bees, purple and rose are the prevailing tints, so much 

 so that, as we all have noticed a hundred times over, they 

 often colour whole tracts of hillside together. The bell- 

 shaped blossoms mark at once the position of the heaths 



Fig. 13.— D! 



s, red spotted with d:trker 

 tubular calyx. 



type of Sileneas with 



with reference to insects ; and the order, according to 

 Mr. Bentham, supplies us with more ornamental plants 

 than any other in the whole world. Among our British 

 species, in the less developed forms, like Vaceiniitm, 

 Arbutus, and Andromeda, the flowers are usually white, 

 flesh-coloured, pinkish, or reddish. The highly developed 

 Erica?, on the other hand, are mostly purple or deep red. 

 E. vulgaris has the calyx as well as the corolla coloured 

 ■with a mauve variety of pink. Mensiesia cant lea is a 

 deep purplish blue. Monotropa alone, a very degraded 



leafless saprophyte form, has greenish yellow or pale 

 brown free petals. 



The Boraginacea; are another very advanced family of 

 Corollijlora>, and they are blue almost without exception. 

 They have usually highly-modified flowers, with a tube 

 below and spreading lobes above ; in addition to which 

 most of the species possess remarkable and strongly- 



Fig. 14. — Night Lychnis, white : adapted to fertilisation by moths. 



developed appendages to the corolla, in the way of teeth, 

 crowns, hairs, scales, parapets or valves. Of the common 

 British species alone, the forget-me-nots (Jfyosotis) are 

 clear sky-blue with a yellow eye ; the viper's bugloss 

 {Echinm vulgare)Ss at first reddish-purple, and afterwards 

 a deep blue ; the lungwort {Pulmonaria officinalis) is also 

 dark blue ; and so are the two alkanets {Anchusa), the 



■ebell, deep Mu 



true bugloss {Lycopsis), the madwort {Asperugo), and the 

 familiar borage {Borago officinalis) ; though all of them 

 by reversion occasionally produce purple or white flowers. 

 Hounds-tongue {Cynoglossum officinale) is purple-red, and 

 most of the other species vary between purple and blue; 

 indeed, throughout the family most flowers are red at first 

 and blue as they mature. Of these, borage at least is 



