CRESCENDO 193 CRETACEOUS SYSTEM readily bestowea large sums upon char- itable undertakings, and in his will left $2,500,000 to found the John Crerar Publie Library, from which sensational novels and skeptical works should be excluded. He died in Chicago, Oct. 19, 1889. CRESCENDO, inci'easing; a gradual increase in the force of sound. Ex- pressed by the sign <, or the abbrevia- tion cres. The sign was first employed in England by Matthew Locke, in 1676. CRESCENTIACE^, crescentiads, an order of perigynous exogens. It consists of small trees, with alternate or clus- tered exstipulate leaver and flowers growing out of the old stems or branches. CRESS, the name of several species of Slants^ most of them of the natural order ruciferse. Water-cress, or Nasturtmm officinale, is used as a salad, and is valued in medicine for its antiscorbutic qualities. The leaves have a moderately pungent taste. It ^ows on the brinks of rivulets and in moist grounds. Common garden cress is the Lepidium sativum; Normandy cress, Barbarea prsscox; win- ter cress, B. vulgaris; Indian cress, Tro- paedlum ma jus; bitter cress, Cardamlne pratensis (cuckoo-flower) . CRESSY. See Crecy-EN-Ponthibu. CRESTON, a city of Iowa and tho county-seat of Union co. Its industries include machine shops, car works, plan- ing mills, and cold-storage plant. It is on the Chicago, Burlington and Quincy railroad. There are a public library, Elks' Home, and other public buildings. Pop. (1910) 6,924; (1920) 8,034. CRETACEOUS SYSTEM, the highest division of the Mesozoic or Secondary strata, rests conformably upon the Jurassic System, and is overlaid uncon- formably by the oldest deposits of the Eocene System. The Cretaceous strata of Great Britain are confined chiefly to the E. and S. E. of England. They form the Yorkshire Wolds, extend over large parts of Norfolk, Suffolk, and Hertford, and compose the Chiltern Hills, Salis- bury Plain, the Downs, and the S. part of the Isle of Wight. On the Continent the Cretaceous rocks form a broad basin in the N. of France, and stretch E. from Belgium, Holland, Denmark, and the S. of Sweden, through the great plains of northern Europe to the S. end of the Ural Mountains; but over extensive re- gions within that wide area they lie more or less concealed under younger forma- tions. There is another extensive de- velopment of Cretaceous strata in south- ern Europe, where they enter largely into the composition of many of the Mediterranean coast-lands. The chief petrological feature of the Cretaceous strata of western and northern Europe is the great development of white chalk in the Anglo-French area, and its grad- ual replacement, when following E. into Germany, etc., by earthy limestones, shales, sand, .ones, etc. The most marked characteristic of the Cretaceous system in southern Europe is the great de- velopment in that region of massive ma- rine limestone (hippurite limestone). In North America Cretaceous strata likewise occur, especially in the Western States and Territories. They also oc- cupy wide tracts in the Gulf States, whence they extend up the Mississippi Valley to the Ohio; they put in appear- ance at interval^ on the Atlantic bor- der between South Carolina and New Jersey, and are met with again on the Pacific border and in the coast-range. Strata of the same age occur also in the far W. of Canada, at the mouth of the Mackenzie river, and in Green- land. In India the system is marked in the Deccan by a massive series of basalt-rocks 4,000 to 6,000 feet thick, and covering an area of 200,000 square miles. In Australia and New Zealand there is a considerable development of these rocks, such as the "desert sandstones" of Queensland, and a small coal-bearing group of beds. In New Zealand, the system contains coals, some of which are lignites while others are bituminous of fair quality. The Wealden Beds con- sist largely of clay and sand, and are almost entirely of fresh-water origin. In Yorkshire, however, the strata which occur on the same horizon as the Weal- den Beds of the S. are of marine origin, as seen in the Speeton clay near Brid- lington. The Lower Greensand, consist- ing of sand, clay, etc., is marine. The gault, a tough blue clay, is likewise ma- rine, and so also are the shallow-water sands of the Upper Greensand, and the thin layer of chalky marl called Chlo- ritic Marl. The most characteristic rocks of the system are the chalk beds. The Cretaceous strata of Great Brit- ain being almost exclusively of marine origin, it is not surprising thar land- plants seldom occur, and that they are met with chiefly in the iresh-water beds near the base of the system. They con- gist chiefly of ferns, cycads, and conifers, a flora resembling that of the preceding Jurassic period. The Upper Cretaceous rocks of Germany, however, have fur- nished many plant remains. Among those are the oldest known dicotyledons, such as extinct species of maple, oak, walnut, beech, laurel, magnolia, etc., also several proteaceous plants. A similar
