AND ORNAMENTAL TREATMENT. 15 



regions are generally thus provided for, while in tropical plants the development of scales is 

 altogether exceptional. Upon the evolution of the bud, the protective work of the scale is at an 

 end ; it is, therefore, thrown off, leaving a scar upon the stem, a memorial of its former existence. 



In the Lilac (Syringa vulgaris) the transition from rudimentary scale to normal leaf form 

 is more gradually marked : fig. 50 is the natural growth of a young Lilac shoot : figs. 51, 52, 53, 

 54. 55i showing the forms detached, as the gradation is thus more readily traced. 



We have already, in referring to plate 3, pointed out the difference in form that may 

 frequently be traced between the earliest leaves of a seedling, and all those that succeed them. 

 Of this the Sunflower (fig. 27) afforded an example; while, in the present plate, we see the same 

 ornamental feature again illustrated in the Radish (Raphanus sativus). We also, in our remarks 

 on that plate,^ pointed out the great variety of form that in some plants is seen in their normal 

 leaves, according to their position on the plant, illustrating our observations by a reference to the 

 forms seen in the Hedge Mustard. The Shepherd's Purse, an equally common plant (figs. 62, 63), 

 is an equally good example, the larger and more richly-cut leaf being one of the lower leaves, 

 while the form of simpler character is one of the higher leaves of the flowering stem. 



Throughout the whole range of ornamental art the use of geometry is a principle of con- 

 tinuous recurrence. In many periods of art, as in the English and Italian Gothic of the 13th 

 century, its use is eminently characteristic. One of our great authorities on matters connected 

 with design has laid down this law, — "All ornament should be based on a geometrical construc- 

 tion ;" and, though at first sight we feel inclined to doubt whether all should be thus bound by so 

 rigid a law, we shall, nevertheless, on consideration and investigation of various examples of 

 ornamental art, be quite prepared to admit the charm that a geometric basis is able to impart to 

 an even otherwise poor design, and to recognise the enhanced beauty that it gives in aill cases. 



Nature affords us many examples of geometrical forms, more especially in the open 

 blossoms of most plants, and perhaps no less so — though it is not at first sight so obvious — in 

 the sections of stems. The circle, the simplest geometrical form, is that most commonly found ; 

 we see it in the stems of grasses, the Elder (Sambucus nigra), the Ash (Xraxinus Excelsior), and 

 many others. The triangle is the typical sectional form of the stems of water plants, as, one angle 

 being presented to the direct action of the flowing stream, it is the form most suited to ensure 

 the necessary stability, acting, as it does, like the prow of a boat, or the triangular pier of a bridge, 

 in diverting the direct force of the current. We see the triangular section very well shown in the 

 Sedges (Carex vulpina, fig. 56), for example : plants that, growing in the bed of the stream, are 

 exposed to the full power of the water ; and again in the Alisma plantago, or ^A(ater Plantain 

 (fig. 57), where the forms are much rounder, as this plant does not grow in the open stream, but 

 fringes its banks, and has not, therefore, so great a pressure to sustain. The contrast between 

 the two triangular forms, each so admirably adapted to the special circumstances of the plant's 

 existence, is, we think, a very striking illustration of that great law of adaptation so frequently 

 to be traced in the works of Nature. The form of the cross section of the stem of the Papyrus 

 (Papyrus antiquoram) is identical with that of the Alisma. Several of the Labiate family have 

 stems based on a square : such a form is seen in the Lamium album — the White Archangel, or 

 White Dead-nettle — fig. 61. We see another modification of it in the stem of the Stinging Nettle 

 (Urtica dioica), and of the square-stalked St. John's Wort (Hypericum guadrangulum) ; while 

 more complex polygonal forms are met with in the pentagonal stems of the Meadow Sweet 

 (Spiraea Ulmaria, fig. 53), or the Stapelia hystrix (fig. i), and in the hexagonal stems of the 

 Balsam (Impatiens noli-me-tangere, fig. 49), or the Hop (Humulus lupulus). A still greater rich- 

 ness of form is seen on cutting across the deeply-furrowed and fluted stems of many of the 

 Umbellifercs, as the Wild Carrot (Daucus Carota), or the Fool's Parsley (^thusa Cynapium). 

 A very curious stem section is figured on plate 3 — that of the Aspidospermum excelsum, a native 

 of British Guiana. Several very remarkable sections of this may be seen in the botanical 

 collection of the British Museum. Though so extraordinary in form, a parallel on a smaller 

 scale might almost be found in the stem of the common Maple (Acer campestre), the bark being 

 exceedingly rough, and full of deep and irregular fissures. Fig. 16, and the remaining illustrations 

 on plate 5, are geometric shaft sections of varying degrees of richness, from the Cathedrals or other 

 buildings named beneath each example. 



D 



