284 MORPHOLOGY. 



A. Sharp folds. 



a. Vernatio duplicativa. Simply folded together (forwards) upon 



the upper surface of the leaf, as in Quercus, Tilia, and the 

 lamina of Liriodendron. 



b. Vern. replicativa. Folded in the same way backward upon 



the under surface of the leaf. 



c. Vern. implicativa. The two borders folded in sharply for- 



wards, as in the perigone of Clematis. 



d. Vern. plicativa. Many longitudinal folds, as is seen, though 



not quite perfectly, in Fagus and Carpinus, but better in 

 Alchemilla, and best of all in Panicum plicatum. 



B. Rounded folds. 



a. Vern. convoluiiva. Simply rolled up, as in Calla and Prunus. 



b. Vern. involutiva. With both edges equally rolled up for- 



wards, as in Alisma and Populus. 



c. Vern. revolutiva. Rolled backwards in a similar manner, as 



seen in Salix and Nerium. 



In leaves curled and folded together the cross way, the most 

 important distinctions occur. 



a. Vern. inclinativa. Incurved forwards, as in the petiole of 



Liriodendron and Hepatica. 



b. Vern. reclinativa. Recurved backwards, as in Aconitum. 



c. Vern. circinata. Rolled up forwards from the point to the 



base, as in Cycas. 



In thefoliatio we distinguish the position of the foliar organs in 

 relation to one another, in general, from the position of individual 

 circles of foliar organs with respect to each other. With regard 

 to the first of these, the conditions have been pointed out. 



A. Foliatio valvata. When the leaves only touch without cover- 



ing each other with their borders. 



a. Fol. valvata sensu stricto, in vernatio simplex. Flower in 



Stapelia. 



b. Fol. induplicativa (?), in vern. duplicativa. 



c. Fol. implicativa^ in vern. implicativa^ as in the perigone of 



Clematis. 



B. Foliatio amplexa. When each leaf embraces all those within it. 



a. FoL convolutiva, in vernatio convolutiva, as in Prunus ar- 



meniaca. 



b. FoL equitans, in vernatio duplicativa^ as in Iris. 



C. Foliatio semiamplexa. When each leaf embraces with one 



edge, and is embraced on the other. 



