

ESSENTIALS OF VEGETABLE PHARMACOGNOSY. 



tion of the parts remaining free. Since its basal attachment, falling entire as a 



the adherent parts are alternating, ad- Calyptra, as in the corolla of Eucalyptus 



hesion necessarily involves the effect of (Fig. 69). A modification of it permits 

 cohesion. In the case of cohesion ex- 



tended very high, peculiar effects, often 

 puzzling to the beginner, are produced, as 

 in the case of the petals and stamens 

 emanating from the summit of the long 

 calyx-tube in Fig. 26. 



Cohesion, like adhesion, may be partial 

 or complete. In its slightest forms, with a 

 mere band of union at the base, it may es- 

 cape observation, as in the case of the 

 corolla of Styrax (Fig. 71). In such cases 

 a decision is best reached by carefully 

 pulling away the corolla in a lateral di- 

 rection. If there is union, however 

 slight, the corolla may thus be removed 

 as one body. Upon the other hand, the 

 petals will occasionally be found held to- 

 gether at the base by agglutination, in 

 which case they can be readily separated 

 without the tearing of any tissue, A 



the remainder of the flower to escape 



peculiar and extreme form of cohesion is 

 that in which the sepals refuse to sep- 



through a rent in the side, as sometimes 

 in the case of the Oenothera (Fig. 70). 

 When the petals are distinct the corolla 

 is said to be Elontheropetalous or Chori- 

 petalous. The older but less desirable 

 term is Polypetalous. When they are 

 coherent the corolla is said to be Gamo- 

 petalous or Synpetalous, the older and 

 less desirable term being Monopetalous. 

 Corresponding terms for the calyx 

 are Eleutherosepalous, Chorisepalous, or 

 Polysepalous and Gamosepalous, Synse- 

 palous or Monosepalous. In the gamo- 

 petalous and gamosepalous state the parts 

 cease to be designated petals and sepals 

 and are known respectively as Corolla- 

 Lobes and Calyx-Lobes. 



The relative altitude to which the co- 

 hesion is carried is indicated by special 

 terms. When existing at the base only 

 the circle is said to be Parted (Fig. 71); 

 when extending about half way up, as in 

 Solanum, Cleft (Fig. 72); when still fur- 

 ther, but yet leaving a considerable por- 

 tion un-united, as in Gelsemium, Lobed 

 (Fig. 73), and when having only traces 

 of the parts un-united, as in Symphytum 

 (Comfrey), Toothed. A peculiar form is 

 that in which the position of the parts is 



arate even at the apex when the flower indicated by a mere waving irregularity 

 expands, and the calyx is torn loose from of the margin, as in the flower of Ipomoea 



