"Riparia gloire should be planted only on rich, deep alluvial soil containing an abundance of plant food and humus, what would be called good garden land, such as river bank soil not liable to overflow. "In most other soils Riparia x Rupestris 3306 is to be recommended, except those that are rather dry, where 3309 is to be preferred, or those which are very wet, where Solonis x Riparia 1616 is surer to give good results." The value of a species or variety for a resistant stock may be judged somewhat by the visible effect of the phylloxera on the roots of the vines. On susceptible species, the punctures of the insects rapidly produce swellings which vary in size and number in accordance with resistance of the species. Technically, the first swelling on the young tender rootlets of the vine is called a nodosity. The presence of a few nodosities on the root system does not indicate that a vine is not a valuable resistant stock. When the nodosity begins to decay and becomes of a cancerous nature, it is called a tuberosity. These tuberosities decay more or less rapidly and deeply, and when they rot deeply cause enfeeblement or death to the vine. Thus, on Vinifera varieties the tuberosities are several times larger and decay sets in much more quickly than on American species which show these tuberosities. Ratings as to resistance of species are usually made from the size and number of the tuberosities, though when these are found producing a scab-like wound which scales off, there may be high resisting power. In order to convey with some degree of definiteness the power of resistance to phylloxera, an arbitrary scale has been agreed on by viticulturists. In this scale, maximum resistance is indicated by 20 and minimum by 0. Thus, the resisting power of a good Vulpina is put as 19.5 and that of a poor Vinifera variety as 0. ADAPTATIONS OF RESISTANT STOCKS TO SOILS AND CLIMATES