cow OF ECOI^OMIC PLANTS. 137 



genus is 0, lulbosum. Its stem is smooth, witli swollen joints, 

 and dissected leaves, bearing on its iDranclies umbels of white 

 flowexs, like the white carrot. It is a native of Europe, and is 

 cultivated in some parts of Germany for the sake of its tubers, 

 which are about the size of a hen's egg ; when well cultivated 

 it is very prolific, and two acres will yield about ten tons of roots. 

 They are very nutritious, and contain a large quantity of starch. 

 They may be dug up in June, but are not perfect till September, 

 when they have the flavour of vanilla, and form a wholesome 

 food. Another tuberous-rooted edible species is C. PrescoUn, a 

 native of Siberia, described as having roots as large as a parsnip. 

 Tuberous roots are also characteristic of the genus Peucedanum^ 

 aUied to the above, represented in this country by P. officincde, 

 known as Sulphurwort ; but the most worthy of notice are 

 P, triternatum and P. nudicaiole, natives of Sierra Nevada and 

 California. They have tuberous roots about the size of nuts, and 

 have a mild sweet taste, and contain much starch and other 

 nutritious matter. They are largely collected by the Indians, 

 and form a large portion of their food. 



Cow Parsnip {Heradeum s;p'ho%dylium). — The common Cow 

 Parsnip is a perennial of the Carrot family (UmbeUiferae), 

 native of this country. Its stem attains a height of 4 to 5 

 feet, bearing broad bipinnate leaves, and large umbels of whitish 

 flowers. It possesses no special property ; toy pop-guns are 

 made of its hollow stems. E, giganteum is remarkable for its 

 great size, attaining the height of 10 to 12 feet, and bearing 

 large umbels of yellow flowers ; it is a native of Siberia. It is 

 the tallest plant of the TJmbelhferae. 



Cow Tree (Brosimum Galactodendron), a tree of the Bread- 

 fruit family (Artocarpacese). This is the Palo de Vaca or Cow 

 Tree, first described by Humboldt. It is a native of Vene- 

 zuela, where it attains a height of from 80 to 100 feet, 

 and forms large forests ; it has oblong pointed leaves of a 

 rusty colour on the under side, strongly veiaed and firm. On 

 incisions being made in the trunk, a copious flow of milky 

 sap is obtained, which is extensively used by the natives as a 



