164 RADIATA war, in which capacity he had a large share in the reorganization of the army. In the cam- paigns of 1813-'14 and 1815 he was chief of the staff of Field Marshal Schwarzenberg, had an important share in the victory at Kulm, and was severely wounded at the battle of Leipsic. In 1831 he took command of the Austrian troops in Italy, and in 1836 was made field mar- shal. During the revolution of 1848, though an octogenarian, he evinced remarkable vigor and equal ability as a commander. From March 18 to March 23 combats between the Austrian troops and the insurgents constantly took place in the streets of Milan. On the latter day Ra- detzky evacuated the city and retreated behind the Mincio, with his headquarters at Verona ; but the advance of Charles Albert at the head of a large army compelled him to retire behind the Adige. After the reduction of Peschiera by the Sardinian army, May 30, he feigned a general retreat, reduced Vicenza, Treviso, and Padua, thus securing his rear, and rapidly re- turned to Verona. His victory at Custozza (July 25) forced the Piedmontese to retreat, and from this time the success of the Austrians was assured. Milan capitulated on Aug. 6, and an armistice of six weeks was agreed upon be- tween Sardinia and Austria. Charles Albert having resumed hostilities in March, 1849, Ra- detzky invaded Piedmont, and on March 23 gained the decisive victory of Novara. He now marched against Venice, which after a protracted siege finally surrendered, Aug. 23. Radetzky was made governor general and mili- tary commander of the whole country, the du- ties of which situation he performed with un- mitigated rigor. On Feb. 28, 1857, at the age of 90, he retired from command. RADIATA, or Radiates, next to the protozoa the lowest of the great branches of the in- vertebrates, whose characteristic feature is that of radiation from the mouth as a centre. All live in the water, and most are marine. They were divided by Agassiz into polyps, acalephs or jelly fishes, and echinoderms, the last class the highest, which have been de- scribed under these titles respectively. As they are among the lowest in rank in the ani- mal kingdom, they are among the earliest in time. Huxley divides the old branch of ra- diates into the subkingdom coelenterata, inclu- ding the hydroids, sea anemones, corals, and acalephs ; and (in part) the subkingdom an- nuloida, including the echinoderms. In the latter subkingdom he places also the intesti- nal and some minute aquatic worms, an. asso- ciation not generally accepted by naturalists. His classification, in detail, is as follows : Sub- kingdom ccelenterata, having the alimentary canal communicating freely with the body cavity; with no heart or circulating system, and in most with no nervous system. Class A, hydrozoa, with walls of the digestive sac not separated from those of the body cavity, with the reproductive organs external; con- taining subclasses I., hydroida (hydroid zo- RADISH ophytes), with orders: 1, hydrida (hydra); 2, corynida (tubularia) ; 3, sertularida (sea firs); II., siphonophora (oceanic), with orders: 4, calycophoridce (diphyes)- 5, physophorida (Portuguese man-of-war) ; III., discojihora (jelly fish), with order 6, medusidce ; IV., lu- cernarida (sea blubbers), with orders : 7, lu- cemariadce ; 8, pelagida ; 9, rhigostomidce ; V., graptolitidce (extinct). Class B, acMnozoa, with stomach opening into body cavity, which is divided into compartments by vertical parti- tions, and with reproductive organs internal ; with orders: 1, zoantharia, with rounded ten- tacles in multiples of five or six, as the sea anemones, star and brain corals, and madre- pores ; 2, alcyonaria, with fringed tentacles in multiples of 4, as alcyonium, tubipores, sea pens, and red coral ; 3, rugosa (extinct) ; 4, ctenophora, oceanic jelly fishes like Venus's girdle and plcurobrachia. In the subkingdom annuloida, the alimentary canal is shut off from the body cavity, and there is a distinct nervous system, generally a blood-circulating system, and a water-vascular system. The only class which concerns the radiates is the echinodermata, with the five living orders of crinoids, ophiurans, star fishes, sea urchins, and holothurians, and the two extinct low orders of blastoids and cystoids, allied to cri- noids. See a series of papers on. " The Mode of Growth of the Radiates," by Prof. Packard, in the "American Naturalist," March, 1875, et teg. RADISH (Lat. radix, root), a cruciferous plant, raphanus sativus (Gr. 04, quickly, and <f>alvetv, to appear, in allusion to its rapid germination), long cultivated for its edible root. The plant has rough and lyrately lobed leaves, the flow- ers purple or whitish and with the structure common to the family ; but the pods differ from those of the other common crucifera in being divided into cells by fleshy false parti- tions. The radish is a hardy annual of which the nativity is uncertain, but it was in cultiva- tion in Egypt in very early times ; being val- ued for its root only, all improvement has been directed toward that part, and it presents a great number of varieties, from the size of a small olive up to those weighing several pounds, and in shape from long and tapering to those much broader than long; some varieties are of very rapid growth, and must be eaten when very young, while others require as long to mature as turnips, and are kept all winter. The radish is to be regarded as a condiment rather than a nutritious food ; in common with cresses, horseradish, and others of the family, it possesses a highly pungent principle which contains nitrogen and often sulphur ; and with the others it is regarded as possessing anti- scorbutic properties. The summer varieties in ordinary culture are sown as early in spring as the soil can be prepared, but they may be had much earlier by sowing in a frame, or at any time during winter if a hot-bed is used. In market gardens, where the greatest econo-
