in large wooden mortars. This pulpy substance is next thrown into a large proportion of clean water, and after the whole has been agitated for some time the fibrous parts are collected in the hand, squeezed, and rejected. The milky liquor which remains is a mixture of the starch with water, and this, after being strained through a hair sieve to separate such fibrous particles as have escaped before, is left for some time to settle, when the water is drained off. The white pasty mass remaining at the bottom is then again washed in a further portion of water, and allowed to subside as before; and this process is sometimes repeated a third time, and oftener even by persons who wish to be exceedingly nice in preparing the powder. When this is considered to be sufficiently cleansed, it is dried on clean white cloths in the sun, and is then fit for consumption; it will keep for a very considerable length of time.

Other plants have been proposed as substitutes for the exotic above described. Among these the arum maculatum, or common wake-robin, has been mentioned. This plant grows wild in woods and on shady banks in many parts of Great Britain.

In its natural state the arum maculatum is exceedingly acrid, so that if a small piece of the leaf be chewed, it produces a painful stinging sensation in the mouth, and by applying the juice of the raw tuber to the skin, this will be considerably blistered. The noxious quality here mentioned, like to that inherent in the cassava root, is, however, extremely volatile, and if the root be either roasted or boiled, and afterwards dried and pounded, it affords a starchy substance which is perfectly insipid, and may be used for the same purposes as the powder of the true arrow-root.

Wake-Robin-Arum maculatum.

Many roots, some the peculiar growth of America, as well as the potato and mandioc, yield substantive food to the inhabitants of both the northern and southern divisions. Among these the SPANISH, or SWEET POTATO-Convolvulus batata-is commonly cultivated for its root in the tropical climates, both of

the eastern and western hemispheres. It was known in this country before the common potato, which, as we have before observed, received its name from the similarity which it bears to the batata.

This plant was introduced into England by Sir Francis Drake and Sir John Hawkins, in the middle of the fifteenth century. Attempts were made to naturalize it in this country, but it was found too tender to thrive in the open air through an English winter. Gerarde cultivated it in his garden in 1597, where it flourished during the warm season; but as soon as it was assailed by the cold weather, it drooped, and perished in the ground. The roots were at that time imported into England in considerable quantities

from Spain and the Canaries; and were used as a confection rather than as a nourishing vegetable. A more abundant supply of fruit of home growth has caused the batata gradually to decline in favour, and for many years it has ceased to be an article of importation into this country.

This plant is an herbaceous perennial, which sends out many trailing stalks, extending six or eight feet every way; these are round, and of a palegreen colour; at each joint roots are put forth, which, in a genial climate, grow to be very large tubers, so that from a single plant forty or fifty large roots are produced. The leaves are angular, and stand on long petioles. The flowers are purple. Several varieties of this plant are to be found in the different countries where it is cultivated, and which differ from each other in size, shape, and the flavour of the roots. The batata is propagated by laying down the young shoots in the spring; indeed, in its native climate it multiplies itself almost spontaneously; for if the branches of roots that have been pulled up are suf fered to remain on the ground and a shower of rain falls soon after they have been broken off, their vegetation will recommence. The roots are sweet, nou

rishing, and though rather insipid, of no unpleasant flavour. In warm climates the batata is of very abundant growth, and easy of propagation; and therefore it is matter of surprise that, in Brazil, the mandioc should be cultivated in preference as food for the negroes, the batata being raised more as a luxury for the planter's table.

In the national garden at Paris this plant is raised in a hot-bed, whence it is transplanted at the latter end of the spring into the open ground, and treated

like the common potato.

In favourable seasons a

tolerable crop is produced; and hopes are entertained that in the course of some years the batata will be so

far acclimatized as to be the object of successful fieldculture in the south of France.

The YAM-Dioscorea sativa-is a native of the East; and is supposed to have been transplanted thence to the West Indies, as it has never been found growing wild in any part of America; while in the island of Ceylon, and on the coast of Malabar, it flourishes in the woods with spontaneous and luxuriant growth. It is very extensively cultivated in Africa, Asia, and America, for its root, which is nutritious and of good flavour, and is used either roasted or boiled as a substitute for bread. This root is farinaceous, and resembles the potato, but is of a closer texture,