M. WICHURA ON THE WINDING OF LEAVES. 283 



whorls toward opposite sides. Eucalyptus punctata, D.C., 

 E.floribunda, Hiigel, E. corymbosa, Sm. Fam. of Myrtaceae : 

 stem-leaves in binate whorls. In each individual whorl the 

 petioles of the opposite leaves are wound towards opposite sides. 

 In the parallel whorls, i. e. those which are separated by an in- 

 termediate, alternating whorl, leaves wound in like directions 

 are found upon the same sides. The same laws of direction are 

 followed by the stem-leaves of a Podocarpus, Fam. of Coniferae, 

 a specimen of which, consisting of a branch without flowers, 

 labelled " ex horto Liverpool/ 5 exists in the General- Herbarium 

 at Berlin. 



47. 



6. Different Metamorphoses of the Leaf. 



Narcissus moschatus, L. : stem-leaves wound to the left, 

 segments of the perianth towards the right, after flowering. 

 ^Echmea, Puya, Pitcairnia, Billberyia, Tillandsia Fam. of Bro- 

 meliaceae: outer perigone wound to the right, the inner to 

 the left, in the bud. Pavetta indica, L., P. caffra, Thunb. &c. 

 Fam. of Rubiaceae : segments of the perianth wound to the 

 right in the bud, the bursting anthers to the left. Lychnis coro- 

 naritty Lam., L. chalcedonica, L., L.flos-cuculi, L., &c. : petals 

 wound in the bud in the direction contrary to the spiral of the 

 sepals, the style wound to the right. The same relation exists 

 between the petals and the appendages of the carpels in the 

 Geraniaceae. Chironiafrutescens,~L., Ch. grandiflora, Lam.: 

 stem-leaves on the alternate whorls wound in opposite direc- 

 tions ; petals in the bud and dehiscing anthers towards the left. 

 Arthrostemma Humboldtii, Fam. of Melastomaceae : sepals 

 wound to the left in the bud, the points of the anthers again to 

 the right. Cistus and Helianthemum : the three larger sepals 

 and the petals wound in opposite directions in the bud, Con- 

 sequently, were it correct (see 45.) that the petals of the Cis- 

 tineae wind in the bud, in the direction opposed to that of the 

 leaf- spiral, the sepals must be wound in the same direction as 

 the latter. 



