SOW THISTLE, the popular name given to a species of a genus of com posite plants, Sonchus. There are about 50 species, mostly herbaceous, but some forming shrubs or small trees. Some of the first may be considered cosmopolitan, while the woody sorts are almost re stricted to the Canaries and to the island of Madeira. The most common species in Great Britain is the common sow thistle, Sonchus oleracens. It is very abundant as a weed, is greedily fed upon by many animals, and is sometimes used on the European continent as a pot-herb. It grows to a height of two or three feet, with a branching stem and small yellow flowers. The S. alpinus forms a tall and fine plant, with fresh and sharply defined foliage and large heads of beau tiful blue flowers. The S. arvensis is found in Massachusetts and southern New York.
SPA, or SPAA, a town of Belgium, and a watering place of world-wide celebrity; in a romantic valley amid hills which form part of the Ardennes chain, 27 miles S. E. of Liege, and 22 miles S. W.
of Aix-la-Chapelle. The prettily-built town consists almost entirely of inns and lodging houses. The mineral springs are efficacious in complaints of the liver, nervous diseases, dyspepsia, etc. Spa water is exported to all quarters of the globe. Spa is also famed for the manu facture of wooden toys, which are stained brown by being steeped in the mineral waters. It was frequented as a watering place as early as the 14th cen tury, and has given its name to many mineral springs. Here the German Great Headquarters were established in 1918, where consultations were held con cerning the armistice and from whence the German delegates set out for the French lines to meet Marshal Foch and sue for peace.