FLOWERS ()!• WASTE PLACES, ETC. 



The robu.sl, ui^riglu, usualU- simple, smooth siL-m ol the Tansy, 

 with its leaflets divided ahnost to tlic base with linely toothed segments, 

 is very characteristic in its habit, it grows in Ixisliy cUimps, excluding 

 all other tender vegetation. 



The small yellowish tlowerheads are arranged in a terminal corymb. 

 the florets are all tubular, or if ligulate longer than the others, and are 

 flat or slightly convex, like buttons. There are no bracts upon the 



flower-stalks. The inner 

 bracts of the involucre 

 arc blunt, the outer not so 

 long, tough, with a mem- 

 branous margin, scarious. 

 The fruit is inversely egg- 

 shaped and 5 -ribbed. 



The stems are usually 

 2 ft. high. Flowers may 

 be souglu in July and 

 August. It is a herba- 

 ceous perennial, increased 

 l)y di\ision of roots, and 

 often culti\ated. 



There are several 

 huntlred florets which 

 form a flat disk, with 

 no ray florets. It is 

 thus, in spite of the ab- 

 sence of the latter, ren- 

 dered conspicuous and ac- 

 cessible to insects, which 

 can pass o\x-r the whole 

 surface and cross-pollinate many florets together, which pollen-seekers 

 find an advantage, and this causes the flower in turn to be much sought 

 after. The honey is easily got at, because the tube is only i mm. deep. 

 The style aids the simultaneous cross-pollination by insect \"isitors. It 

 has a capitate tuft of spreading hairs, and in the first stage presses the 

 pollen out of the cylinder, raising it so that it is swept off by insects, 

 and in the second stage the two lobes spread out with papilla; on the 

 inner side. Tansy is visited by the Hymenoptera, yl/>/s, Co/Zchs, 

 Halictus, Ancircna, Splice odes, Dinetiis, JMelliims, Crabj-o, OdyneTtis; 

 Diptera, Odoii/oiiiyia, Eristalis, Syi'plius, Syritta, j\Iclithrep(cs, Sai-co- 

 phaga; LepidojHera, Polyoiumatits, I'^aiicssa. Hadeiia, Bo/ys; Coleo- 



riu-AO. v.. lUiilev 



Tansv {Tnnace/iim -'ii/ffare, h. 



