— 333 — 



seeming origin of such variegations — their causation being un- 

 known: — all, with a view to the conciseness of the present 

 volume, in the briefest possible terms. 



Normal Markings. 



Generally speaking, the leaves of Agaveae are of a fairly 

 uniform green on both faces or somewhat paler beneath. The 

 ground color differs much in shade in different species and is 

 often masked by a glaucous bloom. Frequently this vanishes in 

 transverse bands which then are more distinctly green than the 

 parts on which the bloom persists, — a fact of which the camera 

 takes more cognizance usuaily than the eye. A. marmomta owes 

 its specific name to such marking. Abrasion of the bloom also 

 gives rise to a variable striate appearance in some cases (e. g. 

 Furcraea Barilletti, Agave Vera Cruz), and the impression made by 

 the margins of contiguous leaves in the bud frequently brings into 

 relief crenated patterns ^). In A. Vidoriae liecjinae and the typical 

 filiferous Littaeas, the cuticle is commonly torn in long strips from 

 young leaves in the bud and adheres to those against which they 

 have been pressed so as to produce a permanent and often decora- 

 tive white or gray marking of the latter, 



Occasionally the leaves are more or less evanescently pur- 

 plish when grown in strong light. In A. Karaffo the edge of 

 young leaves is usuaily narrowly margined with bright red, and in a 

 considerable number of species it is translucently white (e. g. 

 A. sisalana, some forms of .1. pcnduhi) in the young leaves 2), either 

 assuming the usual green color when older {A. simlana), becoming 

 partly or wholly dry and papery (A. Karatto, A. albicans), persisting 

 of a subcartilaginous texture (A. feqidlaua) or developing into a 

 sclerenchymatous, brown or gray, usuaily easily detachable horny 

 Strip connecting the prickles, as in the so-called marginate Littaeas. 



The Upper face is normally marked by a rather wide paler 

 green longitudinal band down the middle in many of the marginate 

 Littaeas (strikingly so in A. Jophantha unio'dfafa and A. Feacockü), 

 in some of the filiferous Littaeas, and in forms of A. pendula. In 

 the marginate species it is also not uncommon for the lower, dorsal, 



') Misinterpretation of an unsuccessful effort to depict these in color lias 

 led to an erroneous siirniise that A. (tittil/annii was originally figured as variegated. 



-) Koch (Wochenschr. Ver. Beförd. Gartenbau 1S(>5: 112) mentions a 

 whitc-margined variety of the normally so-marked A. [Mnufreda) rerolitta. 



