300 M. WICHURA ON THE WINDING OF LEAVES. 



97. 



Asperifoliae. Pulmonaria maritima, and all the species of 

 Myosotis I am acquainted with : segments of the corolla left in 

 the bud. Trichodesma africanum, Lehm. ; Tr. indicum, R. Br. ; 

 Tr. zeylanicuitij R. Br, : points of the anthers wound together 

 towards the left. 



98. 



Convolvulacecs. The corollas of Convolvulus and the allied ge- 

 nera are folded to the right and at the same time wound helia- 

 cally to the left in the bud. See 92. for the contrast in Thevetia 

 neriifolia, Juss., with which, in other respects, the folding and 

 twisting of the corolla before the opening of the flower exactly 

 agree. 



99. 



Hydrophyllea. Nemophila, all the species as yet known to 

 me, and Hydrophyllum virginianum : segments of the corolla 

 right in the bud. 



100. 



Scrophularinece. Pedicularis : the tube of the corolla under- 

 goes a revolution to the left, seldom exceeding ^, during the 

 opening of the flower, whereby the parts of the flower acquire 

 an oblique position. Apparently this revolution commences at 

 that part of the tube which is continued above into the lower 

 lip. This is always most strongly twisted, and it may be clearly 

 detected that the winding of the part of the tube of corolla be- 

 longing to it commences independently and alone before the flower 

 opens, and in a comparatively very young condition. Then, as the 

 part of the tube belonging to the upper lip remains in its position, 

 and the part belonging to the lower lip undergoes a curvature 

 to the left, the left side of the lower lip becomes approximated 

 to the upper lip in the same degree as it is removed from it on 

 the right. The result of this is, that the left side of the lower 

 lip becomes more intimately blended with the upper lip than 

 the right, hence the sinus which separates the upper and lower 

 lips on either side is always cut in deeper on the right than on 

 the left. Pedicularis palustris, L. ; P. asplenifolia, Florke ; P. 

 canadensis, L. ; P. contorta, and P. lanceolata, MX., are species 



