STATISTICS OF THE ORDER CRUCIFERA. 405 
brium Sophia and S. Irio, the latter of which has recently almost 
disappeared. 
The remainder of the Crucifera are either rupestral or alpine 
plants, as many species of Arabis, Draba, Thlaspi, and Hutchinsia. 
Teesdalia is a heath plant, and almost the only plant of the Order 
found on open, heathy parts; Hesperis is a garden plant, and is 
only partially established in some woods, and is occasionally col- 
lected as an outcast from cultivation. If the surface of these 
islands was reduced to its primitive state, or to the condition in 
which it existed before it was reclaimed by man, the number of 
Cruciferous plants spontaneously produced in Britain and Ireland 
would be considerably reduced. Thlaspi arvense is only found 
where the soil is more or less pulverized. Lepidium campestre, Ca- 
melina sativa, Brassica, Sinapis, Raphanus, Erysimum, and several 
Sisymbriums would disappear if cultivation were discontinued. 
About one-third of the Order is dependent more or less on the 
labours of man for their existence in this country; yet man, the 
cultivator at least, would be very glad to get rid of some of them : 
he would “rather have their room than their company.” Several 
are very important as esculents for man and for beast, and many 
are in high estimation as condiments. The useful plants of the 
Order, though occasionally found as weeds, are not very trouble- 
some. It is the useless portion, such as the Shepherd’s Purse, 
the Penny-cress, and, above all, that pest in heavy land, the 
Charlock, that are most difficult to eradicate: these produce 
abundance of seeds, and their seeds are believed to be very tena- 
cious of life, being sometimes buried in the soil for years, yet 
retaiing their vitality and springing up when circumstances are 
favourable to their germination. 
It has been hinted that the number of Crucifere is on the in- 
crease. Lepidium Draba is a recent addition to our Flora, and it 
is now well established in many places, and some of these, as 
the chalk quarries of North Kent, are not likely to be speedily 
disturbed. Camelina, Koniga, and Alyssum are only occasionally 
met with, and their reappearance is very uncertain both in time 
and place ; Iberis is well established in Berkshire and Oxford- / 
shire; Sisymbrium polyceratium is so also in Suffolk; Sinapis / Tre 
dissecta, Lag., is plentiful this year both in Battersea-fields and 
at Wandsworth Steamboat Pier. In the latter locality Stsymbrium 
Columne, Hruca sativa, Rapisirum rugosum, and many other Cru- 
cifere have been aliseored for some years,—a fact which corro- 
