Secondly, from the apparent progress of many animals to greater perfection, as in some insects, as the flies with two wings, termed Diptera; which have rudiments of two other wings, called halteres, or poisers; and in many flowers which have rudiments of new stamina, or filaments without anthers on them. See Botanic Garden, Vol. II. Curcuma, Note, and the Note on l. 204 of Canto I. of this work. It has been supposed by some, that mankind were formerly quadrupeds as well as hermaphrodites; and that some parts of the body are not yet so convenient to an erect attitude as to a horizontal one; as the fundus of the bladder in an erect posture is not exactly over the insertion of the urethra; whence it is seldom completely evacuated, and thus renders mankind more subject to the stone, than if he had preserved his horizontality: these philosophers, with Buffon and Helvetius, seem to imagine, that mankind arose from one family of monkeys on the banks of the Mediterranean; who accidentally had learned to use the adductor pollicis, or that strong muscle which constitutes the ball of the thumb, and draws the point of it to meet the points of the fingers; which common monkeys do not; and that this muscle gradually increased in size, strength, and activity, in successive generations; and by this improved use of the sense of touch, that monkeys acquired clear ideas, and gradually became men. Perhaps all the productions of nature are in their progress to greater perfection! an idea countenanced by modern discoveries and deductions concerning the progressive formation of the solid parts of the terraqueous globe, and consonant to the dignity of the Creator of all things.] "So tulip-bulbs emerging from the seed, Year after year unknown to sex proceed; Erewhile the stamens and the styles display Their petal-curtains, and adorn the day; The beaux and beauties in each blossom glow With wedded joy, or amatorial woe. 130 Unmarried Aphides prolific prove For nine successions uninform'd of love; New sexes next with softer passions spring, Breathe the fond vow, and woo with quivering wing.