Galton's delta

(gawl'tun) [Francis Gallon, English scientist, 1822—1911.] i. more or le well marked triangle, in a finger-print, on either side where the straight ridges, near the joint of the distal phalanx, are succeeded by arches, loops, or whorls (seecut under /j«ger-pn«i5). 2. Tri radius. G.'s law, the law of ancestral inheritance; each parent contributes on an average one-quarter, or (\Y, each grandparent one-sixteenth, or and so on; the occupier of each ancestral place in the «th degree, whatever may be the value of n, contributes (i)^" of the heritage. G.'s system of cla ification, a system of cla ification of finger-prints according to the variations in the patterns of the ridges, which are grouped into arches, loops, and whorls; called the A.L.W., or arch-loop-whorl system. "Arches are formed when the ridges run from one side to the other of the bulb of the digit, without making any back-