Amongst foreign thorny and spiny plants it is very difficult to make a selection.
Theophrastus (one of the very earliest botanists—see p. [37]) describes a class of shrub very common in Phrygia, in which the leaves are produced at the base of the young shoots, which latter end at the top in branch thorns. These thorns, therefore, entirely cover the foliage and keep off that vegetable demon the goat. Some of the Crucifers, Roses, Composites, Labiates, etc., take on this habit in goat-infested countries.[87]
In Egypt, near the Pyramids, one often finds Carlina acaulis, a little thistle which has no stem, but is merely a flower seated in the middle of a rosette of leaves which lie flat on the sand. In the centre there is a circle of sharp spines, each of which is from one to two inches in length. The nostril of a hungry camel or donkey is sure to be pierced if it tries to eat the leaves. The spines of this thistle, like those of our Carline and the Centaurea calcitrapa (thistle of the Bible), spring from the bracts surrounding the flower.
The ancient "calthrops" or "crawtaes" (first used by the Romans) were designed from the spines of the last-named plant[88] (calx, heel, and trappa, snare.) It had four iron spines, so that, however it was thrown down on the ground or in a ford, a spine was sure to stick up and to lame man or horse.
1. Old Roman Calthrops, left on roads, fords, etc., to lame horses.
2, 3. Fruits of Tribulus, showing efficient spines. Animals' feet, in passing, must catch them. They are more efficient than Calthrops.
The Tragacanth plant has also very neat spines. They are the persistent spiny stalks or midribs of the older leaves from which the leaflets have dropped away. The fresh green leaflets are quite protected inside these withered spines.
Several grasses have leaves which end in sharp or needlelike points. One of these, Festuca alpestris, actually produces bleeding at the nostrils of grazing cattle, and is detested by all the shepherds of the Alps.
The Holly is one of our most beautiful trees, as John Evelyn points out: "This vulgar but incomparable tree.... Is there under Heaven a more glorious and refreshing object of the kind than an impregnable hedge of near three hundred feet in length, nine foot high and five in diameter: which I can show in my poor Gardens at any time in the year, glittering with its arm'd and vernished leaves? The taller Standards at orderly distances blushing with their natural Coral."[89] This apparently was the identical hedge into which Peter the Great used to trundle his wheelbarrows. The barrows contained his courtiers. There was a nice run from the top of rising ground close at hand. It was at Sales Court, Deptford.