PHYSIOLOGICAL BOTANY. 271 



in two ranks to the five-ranked, remarking that, when we 

 commence with the posterior single odd rank of leaves, 

 the fourth and third are developed, whilst the first, second, 

 and fifth are not formed. In the same manner he re- 

 duces the three-ranked arrangement of the leaves of Alnus 

 glutinosa to that in five. From the alternate (scattered, 

 says the author, which is, however, the opposite of 

 fascicled} leaves he comes to the opposite leaves, which he 

 regards like the former, not, as at the same height, lying 

 in a transverse section made perpendicular to the axis, 

 but merely approximated and alternating. He proceeds 

 in the same manner with the verticillate, or whorled 

 leaves. This valuable contribution to the theory of the 

 arrangement of leaves deserves great attention ; and it is 

 certainly of importance to consider the angles of the stem 

 in connexion with the arrangement of the leaves. We 

 must connect with this 



On the Arrangement of the Parts of Flowers. By 

 K. S. KUNTH. In the Bericht d. Akad. d.Wissen. Berlin, 

 Feb. 1844. The whole of the elements of a perfect 

 flower, says the author, form several depressed, equally- 

 divided whorls, and may be connected either by one or 

 two spiral lines which run parallel. Hence we must dis- 

 tinguish uni- and bi-spiral flowers. The organic spirals 

 of Dicotyledonous flowers consist typically of five-mem- 

 bered, bi-spiral whorls ; but there are uni-spiral flowers. 

 These usually consist of three whorls ; the sepals form 

 the first whorl, the stamens the second, and the pistil the 

 third. These are the only true apetalous flowers, the 

 other apetalous flowers which occur being readily distin- 

 guishable by the number and position of the stamens ; 

 to these the Thymeleaceae, Polygonacese, &c. belong. The 

 flowers of Monocotyledons are distinguished from those 

 of the bi-spiral Dicotyledons, merely by the three-mem- 

 bered whorl, and thus, like the latter, they also present 

 a calyx and a corolla ; hence it is incorrect to ascribe to 

 them a perigone. I shall merely remark here, that this 



