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Ray (Composite flower the outer)

of a composite flower, the outer or circumferential whorl of florets, as distinguished from those of the disk. In many composites the former are ligulate and the latter tubular. Medullary rays are vertical plates radiating from the pith to the bark through the wood of exogenous stems. In the cross section, the medullary rays constitute fine radiating lines; in a longitudinal section, they impart to the wood a satiny luster, which in the plane, the sycamore, etc., is so marked as to be highly beautiful.

The medullary rays maintain a connection between the bark and the central part of a stem. Carpenters call medullary rays the silver grain. In ichthyology, one of the radiating, bony rods serving to support the fins.

They are of three kinds; (1) Simple; (2) Articulated (showing more or less numerous joints); and (3) Branched (dichotomically split, the joints increasing in number toward the extremity). The differences in the character of the rays in the dorsal fin are an important factor in classification. In optics, etc., a line of light proceeding from a radiant point, or a point of reflection. A collecdepths. They are carnivorous, but by no means active, swimming like the flatfishes by the undulating motion of the pectoral fins, the thin flagelliform tail having entirely lost its locomotive function, and serving merely as a rudder. They may be divided into two groups: (1) rays proper, with a short snout, and (2) skates (attaining a much larger size) with a long, pointed snout. species armed with bucklers or asperities it is the female which has these dermal developments, the male being entirely or nearly smooth. The color also frequently varies in the sexes. The Myliobatidæ are popularly known as eagle rays, the Torpedinidæ as electric rays, and the Trygonidæ as sting rays.

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