The growth of this _Thorn_ may farther argue what in the Second Chapter we supposed; _sc._ That as the proper tendency of the _Lignous Body_, is to ascend, so of the _Cortical_ to descend. For as the _Lignous Thorn_, like other Parts upon the _Trunk_, in its growth ascends; this being almost wholly _Cortical_, pointeth downward. The use of _Thorns_ the very Ingenious Mr. _Sharrock_ observed. Upon the Leaves of divers Plants two Productions shew themselves, _sc._ _Hairs_ and _Globulets_. Of _Hairs_, only one kind is taken notice of, although they are various. Ordinarily they are plain; which when fine and thick set, as on most _Hairy Buds_; or fine and long, as on those of the _Vine_, we call them _Down_. But sometimes they are not plain, but branched out, from the bottom to the top, reciprocally on every side, in some resemblance to a _Stags-Horn_; as in _Mullen_. And sometimes they are _Astral_, as upon _Lavender_, and some other Leaves, and especially those of _Wild Olive_; wherein every _Hair_ rising in one round entire Basis a little way above the Surface of the Leaf, is then disparted. Star-like, into several, four, five or six points, all standing at right Angles with the said perpendicular Basis. The Uses of Hairs are for Distinction and Protection. That of Distinction is but secondary, the Leaves being grown to a considerable size. That of Protection is the prime, for which they were originally form’d together with the Leaves themselves, and whose service they enjoy in their Infant-estate: For the _Hairs_ being then in form of a _Down_, alwayes very thick set, thus give that protection to the Leaves, which their exceeding tenderness then requires; so that they seem to be vested with a Coat of _Frieze_, or to be kept warm, like young and dainty Chickens, in Wooll. _Globulets_ are seen upon _Orach_, both Garden and wild; and yet more plainly on _Mercury_ or _Bonus Henricus_. In these, growing almost upon the whole Plant, and being very large, they are by all taken notice of. But strict Observation discovers, that these _Globulets_ are the natural and constant Off-spring of very many other Plants. Both these _Globulets_, and likewise the diversity of _Hairs_, I find the Learned Mr. _Hook_ hath already observed. They are of two kinds; _Transparent_, as upon the Leaves of _Hysop_, _Mint_, _Baume_, and many more: _White_, as upon those of _Germander_, _Sage_, and others. All which, though the naked Eye will discover, yet by the help of Glasses we may observe most distinctly. The use of these we suppose the same with those of the _Flower_, whereof we shall speak. CHAP. V. _Of the Flower._ We next proceed to the _Flower_. The general Parts whereof are most commonly three; _sc._ the _Empalement_, the _Foliation_, and the _Attire_.