NOTES ON GALLS. 181 



acid flavour, which is disagreeable to most persons ; this is lost by exposing 

 them to the sun, the acidity being thus converted into saccharine matter, 

 and the tubers become as floury as the best varieties of potatoes. The 

 tubers are exposed in Bolivia for ten days in woollen bags, which appear 

 to facilitate the conversion of the acid. If the action of the sun is continued 

 for several months, the Ocas become of the sweetness and consistency of 

 dried figs ; they are then called Carri. 



Bryant describes a root, which he met with on the great prairies of Cali- 

 fornia, and which he called the prairie potato. He considers it in many 

 respects superior to the common potato, and that it might be useful to intro- 

 duce into cultivation. As no scientific description of the plant is given, it 

 is difficult to determine what it is ; for prairie turnip and prairie potato are 

 terms for a very large number of esculent roots in North America, and 

 include some species of Psoralea. A little town called Stowe, in Vermont, 

 uses some 20,000 bushels of a peculiar kind of coarse potato, called the 

 California potato, which yields eight pounds of starch to the bushel. Whether 

 there is any relationship between these potatoes, we cannot state. At least, 

 this subject of new esculent tubers is well worth looking into and testing 

 practically, systematically, and perseveringly. 



NOTES ON GALLS. 



BY M. C. COOKE. 



These excrescences are of so much importance in the arts, that an 

 enumeration of the chief varieties known to commerce may not be altogether 

 devoid of interest to your readers. The papers on dye-stuffs, which have 

 already appeared in these pages, will be hereby augmented by the enume- 

 ration of the galls of Southern Asia, which were purposely excluded from 

 those communications. No attempt has been made at classifying those 

 galls, which are the habitation of a single insect, and are generally of a 

 more or less ligneous character, separately from such as are the home of a 

 colony, and which are commonly hollow and of a horny texture. This 

 paper makes no further pretence than its name indicates, leaving still an 

 opportunity for more precise scientific details. 



Levant Galls. — These are the ordinary galls of commerce, and are 

 produced by the punctures of Cynips gallce tinctorice on the gall oak (Quercus 

 infectoria). They are too well known to need any description. The varie- 

 ties of these galls most recognised are : Mosul galls, named from the place 

 of production, Mosul on the Tigris ; these are the most esteemed. The 

 Bokhara galls are similar, but must not be confounded with another 

 Bokhara gall, produced on a Pistacia. Aleppo galls are not equal to those 

 of the Tigris, for which they are often sold. Tarablous galls are from 

 Tripoli, or Taraplus, and are considered inferior to the Aleppo galls, but 

 are now rarely met with in commerce. Turkey^jgdlXs are the .produce of 



