78 
fully in an Umbrella form, it produces a most novel and inter- 
esting appearance. Much has been done in hybridising these 
plants, and it is likely that many beautiful and singular varieties 
may yet be obtained by the same means, particularly if the sub- 
genera Mammillaria, Melocactus, Echinocactus, Opuntia, 
Periskia, and Rhipsalis, will fertilize the Cereus. In other 
genera, seeds saved from hybrids are found to produce the great- 
est number of new varieties, the existing hybrids of this genus 
ought therefore, in artificial fertilization, to be employed as the 
female parent. 
122 Potatoes, moulding up. Much disparity of opinion oc- 
curs respecting the utility of moulding up Potatoes. Joseph 
Hayward, Esq. in the ninth volume of the Gardener’s Maga- 
zine, objects to the practice altogether, as one not only of inu- 
tility, but of injurious tendency towards the crop. We wish 
that some of our friends would assist in obtaining further proofs. 
Mr Hayward says, “Observing that a farmer, in managing a 
field of potatoes alongside one of mine, did not earth them up, 
but simply flat-hoed the surface of the soil to clear away the 
weeds, while I had mine earthed up with great care, I deter- 
mined on noticing the difference on taking up the crop; and, to 
my astonishment, he had 14 tons per acre, while I had not more 
than half the quantity, and his potatoes were of a more mar- 
ketable quality than mine ; being generally of a good size, while 
mine were large and small. The result induced me to question 
the farmer ; and he told me it was a practice he had followed 
for many years, as he thought the earthing up was worse than 
labour thrown away; that, a year or two before, he had obtain- 
ed 19 tons per acre by the same management. This statement 
put me upon considering the principles upon which such a re- 
sult was founded; and it appeared to me that, by drawing up 
the earth over the potato, in sloping ridges, it was deprived of 
its due supply of moisture by the rains ; for, when they fell, the 
w ater was cast into the ditches. Further, in regard to the idea 
that, by thus earthing up, the number of tubers is increased, 
the effect is quite the reverse; for experience proves that a pota- 
to placed an inch only under the surface of the earth will pro- 
duce a greater number of tubers than one planted at the depth 
of a foot. From reasoning thus, I determined to adopt the 
practice: however, such is the force of prejudice, that I have 
