IN EXTRA-TROPICAL COUNTRIES. 343 



success by conveying the Truffle in its native soil and locating it 

 in calcareous places of forest regions. As a condiment, or merely 

 in a roasted state, it affords an aromatic food. The famous 

 Quercy or Perigord Truffle is derived from this species. T. 

 melanosporum (Vitt.), from France, Germany, and Italy, is of a 

 still more exquisite taste than T. cibarium indeed, of strawberry 

 flavour. 



Tuber magnatum, Pico. 



Grey Truffle. South Europe. One of the most esteemed Truffles, 

 with some garlic flavour. Hymenogaster Bulliardi (Vitt.), and 

 Melanogaster variegatus (Tulasne) of South Europe are also excel- 

 lent Truffles. 



Tuber rufum, Pico. 



Red Truffle, especially in vineyards. Much used for food, but 

 smaller than the Terfezia Truffles. 



Ulex Europaeus, Linne. 



Middle and South Europe, Azores, Canary Islands. The Whin, 

 Gorse, or Furze. A bush important for covering quickly drift- 

 sands on coasts. Too apt to stray as a hedge plant. 



Ullucus tuberosus, Lozano. (Melloca tuberosa, Lindley). 



Andes of New Granada and Peru, up to an elevation of 9,000 feet. 

 A perennial herb, the tubers of which are edible. 



Ulmus alata, Michaux. 



The Whahoo Elm of North America. Of quick growth, unwedge- 

 able, extending to Newfoundland and Texas. Height of tree, 40 

 feet. Wood fine-grained, heavier and stronger than that of the 

 White Elm, of a dull-red colour, used by wheelwrights, but like 

 that of U. Americana not equal to the European Elm. 



Ulmus Americana, Linne. * 



The White Elm of North America, also called Rock or Swamp 

 Elm. A tree of longevity, fond of moist river-banks. 100 

 feet high, trunk 60 feet, 5 feet in diameter. Manning men- 

 tions that trees have been known to attain a circumference of 27 

 feet at 3 feet from the ground, and of 13 feet where the 

 branches burst forth. It is highly prized for street-planting in 

 North America. Can be propagated like the European Elm from 

 suckers. Almost indifferent to soil. The timber is light, used for 

 wheelwrights' work, for tubes, water-pipes, bears driving of bolts 

 well (Robb). It is durable if either kept quite dry or permanently 

 submerged in water. TJ. floridana (Chapman) is a variety. 



