M. WICHURA ON THE WINDING OF LEAVES. 291 



direction. Perhaps the direction of the leaf-spiral has an influ- 

 ence here in the direction of the winding, producing, by its 

 difference in different specimens, a corresponding difference in 

 the direction of the winding leaves. I have no exact observa- 

 tions on this point. 



Butomacece. Butomus umbellatus, L. : stem-leaves left. 



65. 



Juncacece. Xerotes mucronata, R. Br. ; X. aemula, R. Br. ; 

 X. effusa, Endl. ; X. suaveolens, Endl. ; X. rupestris, Endl. ; 

 X. micrantha, Endl.; X.flexifolia, R. Br. ; X. rigida, R. Br. ; 

 X. longifolia, R. Br. : stem-leaves left. Xerotes umbrosa, Endl., 

 and two species from Major Mitchell's Expedition, distributed 

 unnamed under the Nos. 542 and 564 : stem-leaves right On 

 the doubly-wound leaves of Xerotes purpurea, Endl., see 43. 

 The stem-leaves of some species of Juncus, in particular Juncus 

 compressuSy Jacq., seem to behave like the stem-leaves ofScheuch- 

 zeria. In many specimens the leaves wind to the left, in others 

 to the right; the right- winding predominate. Luzula albida, 

 D.C. ; L. campestris, D.C. ; anthers after dehiscence left. The 

 stigmas of all the species of Juncus and Luzula with which I am 

 acquainted wind to the left before the flower opens. 



65*. 



Melanthacece. Tofieldia calyculata, Wahlenb. ; Colchicum 

 Szovitsiiy Fisch. et Meyer ; C. autumnale, L. ; C. variegatum, 

 Bivon : stem-leaves left. Merendera caucasica, M. B. : stem- 

 leaves slightly right. 



66. 



Liliacea. Ornithogalum umbellatum, L. ; 0. Gussonii, Ten. ; 

 O. lanceolatum, Labill. ; Bulbine annua, Willd. ; Johnsonia mu- 

 cronata, Endl., as well as all the numerous species of the genera 

 Lilium, Eremurus and Asphodelus I have seen : stem-leaves right. 

 Hyacinthus orientalis, L. ; Thysanotus proliferus, Lindl. ; Tul- 

 baghia alliacea, L.; T.cepacea,ii.; AcanthocarpusPreissii 9 Lehm.: 

 stem-leaves left. In the genus Fritillaria occur species with 

 left- and with right-winding leaves. To the former belong, for 

 example, F. imperialis, L. ; F. Meleagris, L., &c. ; to the latter, 



19* 



