144 IRIS VERSICOLOR. BLUE FLAG. 



but the normally distinct parts have been so united that their 

 trifid character is only revealed by the three-parted stigma at 

 the apex. If now we revert again to the Iris, we shall find but 

 a single verticil of stamens, — three only; but these are in their 

 proper situation, or in other words, they alternate with the petals, 

 and bend back over the median line of the sepals. The other 

 three which we might expect to find, judging from the analo- 

 gous structure of the Lily, have wholly disappeared. As regards 

 the pistils, they would almost seem to be wanting, at first sight, 

 and in the place which they ought to occupy, we notice a peta- 

 loid, three-parted structure in the centre of the flower, inside 

 of the stamens. On closer examination, however, we discover 

 that these structures are really the pistils, and that they have 

 coalesced with another set of three bodies which might have 

 formed a second verticil of three stamens, but which are still 

 petaloid in character. From the morphological lessons w r e have 

 already learned, we can now understand what has become of the 

 second verticil of stamens. These organs have evidently been 

 united with the next verticil, or the pistils, and thus we have the 

 beautiful petaloid pistils, which give such a peculiar character 

 to the Iris. 



Our plant abounds in Maine in the East, and in Minnesota in 

 the West, and is as much at home in Arkansas as in Florida, 

 and throughout the whole of the vast territory of which these 

 points indicate the limits. 



According to Lindley, the Blue Flag is a " diuretic, purgative, 

 and emetic." Bartram, in his " Travels," tells us that it was in 

 great favor with the Indians as a powerful cathartic; and in- 

 deed he intimates that its wide distribution is in a great meas- 

 ure due to the estimation in which it was held by them for 

 medicinal purposes. It has also been found useful in cases of 

 dropsy. In overdoses, it causes nausea, similar to sea-sickness. 



EXPLANATION OF the Plate. — I. Flowering stem, proceeding from the terminal bud of 

 a rhizome of last year's growth. — 2. Branchlet of the ilower stem, with expanded flower. 

 — 3. Faded flower. — 4. Cross section of the ovary. 



