4.06 
The diseases of potatoes are chiefly the scab, the worm, and 
the curl. The scab, or ulcerated surface of the tubers, has 
never been satisfactorily accounted for. Some attributing it to 
the ammonia of horse-dung, others to alkali, and some to the 
use of coal ashes. Change of seed, and of ground are the only 
resources known at present for this malady. The worm and 
grub both attack the tuber; and the same preventative is re- 
commended. The only serious disease of the potatoe is the 
curl ; and this is now ascertained to be produced by the con- 
centration of the sap in the tuber; and this concentration, 
or thickening, is prevented by early taking up. This discovery 
was first made by the farmers near Edinburgh observing that 
seed potatoes procured from the moors, or elevated cold ground, 
never suffered from the curl; and it consequently became a 
practice, every 3 or 4 years, to procure a change of seed from 
these districts. On inquiry, it was found that potatoes of these 
upland grounds continued in a growing state till the haulm was 
blackened by the first frosts of October. They were then taken 
up, when, of course, they could not be ripe. Subsequent expe- 
riments has established the fact, that the curl is prevented by 
using unripe seed. It is also a safe practice frequently to 
change the seed, and also to change the variety. 
Tuberous-rooted Nightshade, or Common Potatoe. 
Sept. Clt. 1597. Pl. 1 to 2 feet. 
2 S. ETUBERÒsUM (Lindl. bot. reg. 1712.) rhizoma thick, 
subterraneous, without tubers; stem herbaceous; leaflets un- 
equal, complicate, much undulated, approximate : alternate ones 
minute; pedicels articulated; calyxes and corollas 5-angled, 
glabrous. 0/4. H. Native of Chili. Habit of S. tuberósum ; 
but the roots are without tubers: the flowers larger, on shorter 
pedicels ; the calyx glabrous and shining, not hispid. Corollas 
purple. There is a variety of S. tuberdsum with long, creeping 
rhizoma, without tubers, and white flowers, in the botanic gar- 
den of Chelsea, from Chili, which renders the present rather 
doubtful as a species. We suspect that this and $. Commersdnii 
are only varieties of S. tuberdsum. The S. stoloniferum, Cham. 
in Linnea, 8. p. 255. a native of Mexico, also appears to be a 
variety of S. tuberdsum. 
Tuberless Nightshade, or Potatoe. Fl. July, Oct. Clt. 1833. 
Pl. 1-2 feet. 
3 S. Commersoni (Poir. suppl. 3. p. 746. Dun. sol. ed. 2d. 
ined. t, 133. syn. p. 5.) herbaceous; leaves pinnate, sublyrate, 
pilose; pedicels articulate; corollas 5-cleft. 2. H. Native 
of America, about Monte Video, Commerson. Hort. trans. 5. t. 
10. Very nearly allied to jS. tuberdsum ; but the root is un- 
known ; it differs, however, from that plant, in the leaves being 
more profoundly pinnatifid ; but the leaflets are sessile, and not 
alternate, unequal; the terminal leaflet very large; and the 
corolla is 5-cleft, not 5-angled. 
Commerson's Nightshade, or Potatoe. 
1822. Pl. 1 to 2 feet. 
4 S. APPENDICULA'TUM (Dun. syn. p. 5. H.B. et Kunth, 
nov. gen. 3. p. 19.) shrubby? or herbaceous? scandent; leaves 
quinately impari-pinnate, stipulate at the base; leaflets oblong, 
acuminated, beset with adpressed hairs above, but downy on the 
veins beneath; corymbs terminal, few-flowered. h.? G. 
Native of Mexico, near La Puente de La Madre de Dios, be- 
tween Totonileo el Grande and Actopan. Branchlets puberu- 
lous. Leaflets opposite, terminal one large. Corymbs puberu- 
lous. Corolla 5-cleft, white, glabrous, with oblong, acute seg- 
ments. Calyx half globose, 5-lobed. 
A ppendiculate-leaved Nightshade. Fl. June, Aug. Clt. 1823. 
Shrub climbing. 
5 S. pinna’tum (Cav. icon. 5. p. 23. t. 439. f. 1.) stem her- 
baceous, furrowed ; leaves impari-pinnate ; leaflets decurrent ; 
Fl. May, 
Fl. May, Oct.. Clt. 
SOLANACEEX. 
J. Sonanum. 
flowers terminal, corymbose. 2%. H. Native of Chili, near 
Coquimbo. Stem almost winged from the decurrent leaves. 
Leaves with 3 pairs of leaflets. Branches of corymbs dichoto- 
mous. Corollas deep yellow. Berry glabrous, black, size of 
a pea. 
Pinnate-leaved Nightshade. PI. 2 feet. 
§ 2. Leaves impari-pinnate. Racemes corymbose, lateral. 
6 S. Carpa'sir (Dun. syn. p. 6. H. B. et Kunth, nov. gen. 
amer. 3. p. 19.) herbaceous; leaves impari or unequally pin- 
nate, soft from tomentum, whitish beneath; racemes dichoto- 
mous, cymose. %. H. Native of Quito, near Chillo. Dun. 
sol. ed. 2d. ined. t. 85. f. 2. This species differs from S. 
ochránthum, which it is very like; in the stem being herbace- 
ous; in the leaves being smaller; the leaflets being 3-pair ; 
and in the racemes being spreading and cymose above; in the 
cymes being longer; and in the flowers being larger. 
Caldas's Nightshade. PI. climbing ? 
7 S. Jame su (Torrey, in ann. lyc. 2. p. 227.) herbaceous, 
rather pilose; stem unarmed, erect; leaves impari-pinnate ; 
leaflets ovate-lanceolate, abruptly narrowed at the base, obso- 
letely sinuated ; racemes extra-axillary, few-flowered. ©. H. 
Native of the Arkansas? Racemes about 4-flowered. Flowers 
white. 
James’s Nightshade. PI. 4 to 3 foot. 
8 S. ocura’ntHUM (Dun. syn. p. 6. sol. ed. 2d. ined. t. 85. 
f.1. H. B. et Kunth, nov. gen. 3. p. 20.) shrubby, scandent ; 
leaves interruptedly pinnate, hairy above, but clothed with 
white tomentum beneath; leaflets oblong, nearly entire; co- 
rymbs lateral, subdichotomous, on long peduncles, about equal 
in length to the leaves. kh. J. G. Native of Quito, near 
Chillo. Leaflets opposite, 4 pairs. Corymbs hairy. Corolla 
5-cleft, yellow, hairy outside ; segments acutish, rather un- 
equal. 
Yellom-flowered Nightshade. Shrub climbing. 
9 S. sucLANDrEOLIUM (Dun. syn. p. 6. sol. ed. 2d. ined. t. 
86.) shrubby, scandent; leaves impari-pinnate, rough from 
hairs above, but clothed with soft hairs beneath; leaflets 
oblong, subcordate, quite entire; corymbs lateral, dichotomous, 
divaricate. h.. S. Native of New Granada, in the pro- 
vince of Pasto, in humid places near Tusa et Cuesaca. H. B. 
et Kunth, nov. gen. 3. p. 20. Leaflets opposite, 3 pairs, on 
short petioles: terminal one rather the largest. ^ Corymbs 
pilose. Corolla 5-parted, white? pilose outside. 
Walnut-leaved Nightshade. Shrub climbing. 
§ 3. PrTEROrDEA (from mrepov, pteron, a wing; and «oc, 
eidos, form ; in reference to the pinnate leaves.) Leaves impari- 
pinnate or ternate; leaflets quite entire, acuminated. — Peduncles 
axillary, aggregate, racemose. 
10 S. mre (Ruiz. et Pav. fl. per. 2. p. 38. t. 173. f. a.) 
stem herbaceous, radicant ; leaves impari-pinnate; leaflets ob- 
long; racemes axillary, aggregate; berries globose. ©. H. 
Native of Peru, in the province of Panatahua, in forests at 
Pozuzo and Chincao, in humid places.  Glabrous. Stem 
bluntly angular. Flowers small, secund, white. Berry white, 
size of a pea. Leaves 8-10 inches long. 
Mild Nightshade. PI, 2 feet, creeping. 
11 S. conicum (Ruiz. et Pav. l. c. t. 172. f. b.) stems her- 
baceous ; leaves impari-pinnate ; leaflets oblong-lanceolate; pe- 
duncles axillary, usually 3 together, spicate ; berry conical. 
©. H. Native of Peru, in groves at Chincao and Cuchero. 
Stem pilose, and angular at top. Peduncles solitary, twin or 
tern, almost the length of the petioles, recurved at top. 
LUSSO 
