1 4 PARTS OF FERNS. 



slightly indented in various ways such as " serrated," which means toothed like a saw i 



" fimbriated" when the serration extends as corrugation within the edge ; " crenate," 



hollowed into rounded notches ; " crenulate" when these notches are small ; and 



" lobed" when the projections between the notches are more or less rounded. As the 



first two of the above terms are often used, in other senses, in reference to parts of 



fronds, I shall follow the Synopsis in employing the word " undivided" ; though even 



this is hardly a satisfactory one, because division begins as soon as an edge is broken. 



" Serrated," " crenate," &c., are also used in respect of the edges of the sub-divisions 



of fronds as well as those of whole ones ; and when an edge is not indented in any 



way it is said to be " entire." A margin is called " curled" or " crisped" when it is 



waved up or down like the corrugations of roofing-iron. When the edge of a frond, 



or of any portion of it, is indented right down to the midrib, it or that portion is said 



to be " pinnate," and the projections between the indentations are called " pinnae" 



(pinna, in the singular) ; but if the indentations stop just short of the midrib, it is 



called " pinnatipartite" (pinnately divided), or about half-way, " pinnatifid" (pinnately 



cleft) ; and the projections are either " pinnae," " pinnules" (pin-nu-les), or " lobes," 



according to their depth, in proportion to their width, their situation on the frond, and 



their being rounded or pointed at the ends : the first term being more applicable to 



the pointed ones. If the pinnae are again sub-divided, right down to their midribs, the 



frond is said to be " bi-pinnate" ; and if a third or fourth division occurs, it is " tri- 



pinnate" or " quadripinnate" ; and the same with the other terms. Beyond this, a 



frond is said to be " de-compound" ; and this term is sometimes used even to tri and 



quadripinnate ferns. It must be clearly understood that these terms apply to the 



largest and most divided part of a frond. The upper end of a frond is usually less 



divided than the lower one ; and some fronds taper both ways, irt which case they are 



usually most divided just below the middle. They also apply to large fully-developed 



fronds on old plants, as the smaller fronds on young plants are usually less divided. 



It is necessary to bear this in mind, as otherwise anyone gathering a frond less divided 



than the description says, might fail to identify it. The end portion of a frond, beyond 



where the lateral pinnae branch out right and left, is called the " terminal pinna", and 



the same term is used to express the end portion of a main pinna when the frond is 



bipinnate or more divided. The end part of a pinna, particularly of a secondary or 



tertiary one, is similarly called the " terminal pinnule." The terminal pinna or pinnule 



usually tapers down, being first pinnatipartite, then deeply pinnatifid, then less and 



less so, and then merely lobed, till it ends in a point or tail. The ultimate divisions 



of a frond are called " pinnules" (pin-nu-les, little pinnae) or " segments." The former 



term applies most strictly where, as in the Adianta (maidenhair ferns), they are of a 



leaf-like character ; but it is also employed in the other cases, for want of a better 



one. Pinnae and pinnules are sometimes connected with the rachis or midrib of the* 



