And Philo subjoined: There is, Crato, a reason for this amongst the philosophers, which the gardeners confirm and strengthen. For they say, oil is very hurtful to all plants, and any plant dipped in it like a bee, will soon die. Now these trees are of a fat and oily nature, insomuch that they weep pitch and rosin; and, if you cut then gore (as it were) appears presently in the wound. Besides, a torch made of them sends forth an oily smoke, and the brightness of the flame shows it to be fat; and upon this account these trees are as great enemies to all other kinds of grafts as oil itself. To this Crato added, that the bark was a partial cause; for that, being rare and dry, could not afford either convenient room or sufficient nourishment to the grafts; but when the bark is moist, it quickly joins with those grafts that are let into the body of the tree. Then Soclarus added: This too ought to be considered, that that which receives a graft of another kind ought to be easy to be changed, that the graft may prevail, and make the sap in the stock fit and natural to itself. Thus we break up the ground and soften it, that being thus broken it may more easily be wrought upon, and applied to what we plant in it; for things that are hard and rigid cannot be so quickly wrought upon nor so easily changed. Now those trees, being of very light wood, do not mix well with the grafts, because they are very hard either to be changed or overcome. But more, it is manifest that the stock which receives the graft should be instead of a soil to it, and a soil should have a breeding faculty; and therefore we choose the most fruitful stocks to graft on, as women that are full of milk, when we would put out a child to nurse. But everybody knows that the fir, cypress, and the like are no great bearers. For as men very fat have few children (for, the whole nourishment being employed in the body, there remains no overplus to make seed), so these trees, spending all their sap in their own stock, flourish indeed and grow great; but as for fruit, some bear none at all, some very little, and that too slowly ripens; therefore it is no wonder that they will not nourish another's fruit, when they are so very sparing to their own. QUESTION VII. ABOUT THE FISH CALLED REMORA OR ECHENEIS. CHAEREMONIANUS, PLUTARCH, AND OTHERS.