2,lS 
MORPHOLOGY OF MEMBERS. 
forming spines, becoming transformed into conical, pointed, hardened bodies. 
This may take place either by the whole shoot or even a whole branch-system 
becoming spiny, with suppression of the foliage-leaves, as in the branched spines 
of Gleditschia ferox, or by the shoot first producing foliage-leaves, growing in the 
ordinary manner, and finally finishing its growth in length by a spiny point, as 
in the lower axillary shoots of Gleditschia iriacanthos, Prunus spinosa, and many 
others. 
Among Phanerogams, especially Monocotyledons and Dicotyledons, displacements of 
the leaves and lateral shoots (as well as roots), and adhesions of members, constantly occur, 
which, as development advances, are in apparent contradiction to the typical laws of 
growth and local position which are the ordinary ones in these classes ; and it appears 
Fig. 157. — Diagram of the adhesion of leaves FiG. 158. — Herniinuim Monorchis (after T. Innisch : Biologie 
with the axial parts of their axillary shoots (after und Morphologie der Orchideen. Leipzig 1853) ; / the lower part 
Nägeli and Schwendener ; Das Mikroskop). of a flowering shoot (natural size) ; //, /// the part containing the 
bud (magnified). 
impossible to apply even the most general rules of growth which we have now been con- 
sidering. It would be difficult for even a clever beginner to explain by the principles which 
have been regarded in this chapter as most universal, the structure, for instance, of the ex- 
panded flower of an Orchis, Rose, Lamium, Sal'via, or of many other plants, of a partially or 
wholly ripe fig, or the phyllotaxis in the inflorescences of Borragineae and Solanacese and 
many others. But the history of development shows that even such cases may be ranged 
under these laws, and that peculiarities of structures of this kind only arise at a later 
period, or in such a manner that they confirm general rules. The deviations from these 
laws are caused by the cessation of the growth of particular parts at an early period, while 
others undergo a great advance ; or they are caused by the adhesion of parts originally 
distinct. Although it is quite impossible to give general rules for the explanation 
