100 
CHEMISTRY OF HORTICULTURE. 
MINA LOBATA. (Lobe-leaved Mina.) 
Class, Pentandrfa. Order, MoNOGVNrA. Nat. Order, CoNvoLvuLACEiE. 
Gkneric Character.— CaZ?/^ short, naked, five-parted. 
Corolla hypocrateriform ; tube short, and much thrust into 
the inflated limb ; limb campanulate, inflated, five-sided, 
and terminating in five h)bes. Stamens unequal, attached 
to the tube, exserted. Ovary four-celled. Ovules solitary. 
Stigma capitate. 
Specific Character — Plant a twining biennial. Stems 
glabrous, terete. Petioles an inch or more long, smooth. 
Leaves cordate, three- lobed, slightly villous beneath, gla- 
brous, and of a bright green above. Peduncles long. Racemes 
forked, each part bearing nine to twelve flowers. Calyx 
green, tinged with red, short and fleshy ; divided into five 
oblong, keeled, acute segments. Corolla tube short, orange- 
yellow ; limb half an-inch long, at first of a rich and brilliant 
carmine colour, but changing as it expands to deep orange, 
and becomes finally of a pale yellow ; lobes small, rounded. 
Stamens inserted in the mouth of the tube ; filaments long, 
slender; anthers kidney-shaped, attached by the middle, 
yellow. Ovary surrounded by a small fleshy gland. 
Authorities and Svnonvmes Mina, La Llave. Q,ua- 
moclit, Tourne/ort, and other Botanists. Exogonium, Mo- 
fino, and others. Morenoa, La Llave. Mina lobata, La 
Llave and Lexarza, Novorum Veget. des. fas., i. 3. ; Dr. 
Lindley, in Bot. Reg., v. xxviii., Miscel. 9, t. xxiv. Q,ua- 
moclit Mina, Don's Gard. and But., v. iv., p. 259. 
This handsome Convolvulaceous plant is a native of Mexico, whence it was introduced by 
G. F. Dickson, Esq., in 1842, who presented it to the Earl of Burlington, and in whose 
gardens at Holker, under the superintendence of Mr. Wilson, it flowered for the first time 
in November, 1843, when our drawing was prepared. Subsequently it has been introduced 
to other collections. 
In habit the plant greatly resembles some species of Ipomcea with lobed leaves, but 
the flowers are produced in forked, many-flowered racemes, a character very unusual in 
this Order. The individual flowers are also singularly formed, very different from those 
of any other plants belonging to Convolvulacea ; so that, when the leaves are removed, it 
could scarcely at first sight be recognised as belonging to the Order under which it is 
placed : the structure of the ovary and stigma, however, is that of true Convolvulacece. 
It is an annual, requiring the temperature of a greenhouse. The seeds should be 
sown in pots, and placed in heat ; when the young plants have become of a sufficient size, 
they must be transplanted into small pots, and shifted from size to size as they advance 
in growth. 
A light rich soil, composed of equal parts of loam, decayed leaves, and heath-mould, 
suits them best. Increase is not only effected by seeds like other annuals, but they may 
be likewise propagated by cuttings, separated as soon as the wood is sufficiently matured, 
and planted in pots of sand, and placed under a glass in heat. 
The name is given in honour of Don Francisco Xavier Mina, a Mexican minister. 
CHEMISTEY OF HORTICULTURE. 
By John Towers, Esq. 
As an opportunity has, by the new arrangement of this Magazine, been furnished to 
introduce the above subject, I avail myself of it. Chemical terms are in the mouth of 
every cultivator; but the mere use of such, without an appreciation of their due sense and 
meaning, conveys little instruction. It is proposed, therefore, to enter upon a series of 
Chemical Articles, of which this is the leader ; wherein, beginning with first principles, no 
one word that does not convey its own application, shall be passed over without an attempt, 
at least, to render it familiarly intelligible. In order to avoid error and the appearance of 
dogmatism, I shall faithfully appeal to the writings of some of our ablest philosophers ; but 
while so doing, as it is admitted that knowledge, though rapidly advancing, is still far from 
perfect, I will not scruple to offer, by way of comment, any remark that may tend to 
elucidate phenomena or elicit truth, in order to induce a research of causes, and thus to 
establish the foundations of a consistent philosophical theory. 
