PLUMBAGINEAE 



55 



LXIII. ORDER PLUMBAGINEAE JUSS. 



Literature. Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' p. 122. 



Flowers small but brightly coloured, and arranged in heads or corymbs. Nectar 

 secreted and concealed in the bases of the flowers, which therefore belong to class 

 C or S. Fritz Mijller states that many species of Plumbago and Statice are dimor- 

 phous (Bot. Ztg., Leipzig, xxvi, 1868, p. 113). 



536. Armeria L. 



1790. A. elongata Hoffm. ( = A. vulgaris WiUd., Statice Armeria Z., and 

 S. elongata Hoffm.). (Sprengel, ' Entd. Geh.,' pp. 174-5; Treviranus, Bot. Ztg., 

 Leipzig, xxi, 1863; MacLeod, Bot. Centralbl., Cassel, xxix, 1887; Knuth, op. cit., 

 xlviii, 1891, 'Vergl. 

 Beob.,' 'Bl. u. Insekt. 

 a. d. nordfr. Ins.,' pp. 

 122-3, ' Weit. Beob. ii. 

 Bl. u. Insekt. a. d. 

 nordfr. Ins,' p. 239, 

 'Bl. u. Insekt. a. d. 

 Halligen ' ; Kerner, 

 'Nat. Hist. PI.,' Eng. 

 Ed. I, II, p. 358; 

 Schulz, ' Beitrage,' I, 

 pp. 89-90.) The 

 plants of this species 

 which I have investi- 

 gated in the North 

 Frisian Islands belong 

 to a variety often 

 reckoned as a distinct 

 species (A. maritima 



Willd.). The flowers smell of cumarin, and the conical calyx, about 5 mm. in length, 

 possesses a membranous limb of bright-violet colour like the corolla, and strengthened 

 by five stiff teeth, the reddish tips of which enhance conspicuousness. The five 

 corolla-lobes alternate with these teeth, are 8 mm. long and 5 mm. broad, and only 

 connected at their bases. Each of them is traversed by a strong median vein of 

 darker colour, and two weaker lateral ones. These lobes are held together by the 

 calyx so as to constitute a funnel-shaped tube about 7 mm. deep. The stamens are 

 4-5 mm. long and opposed to the petals. Upon the top of the ovary there is 

 a green five-rayed nectary, from the middle of which spring five styles equalling 

 the stamens in length. The lower third of these is beset with erect white hairs, 

 which are particularly long and numerous above, making up a dense feltwork 

 serving as an effective protection to the nectar. The terminal third of the styles 

 is beset with papillae giving a velvety surface. MacLeod says there is a nectary 

 at the base of each petal. 



In the island of Sylt the flowers are feebly protandrous, indeed almost homo- 

 gamous. The erect stamens dehisce as soon as the flowers open, so that insects 



Fig. 234. Diapensia lappontca, L. (after E. Warming). Drawn from 

 material collected in Greenland. A. A widely open flower, seen from above, 

 showing that the anthers are remote from the stigma. B. Corolla and 



stamens, seen from the side. C. Pistil and petal from the same flower. 



D, E. Pollen-grains. F. A young flower with corolla only partly expanded ; 



the anthers have dehisced and there are some pollen-grains upon the stigma, 

 which is already receptive ; anthers and stigma are so close together that 

 autogamy is probably easj-. G. A young flower partly dissected ; the anthers 

 have opened and the stigma is receptive. H. Trifid style. {A, B, C x 2^; 

 G X 3i.) 



