830 
Recent Agricultural Publications. 
a green mantle, the recently tilled land. It is, as it were, the 
first earnest of the coming reward for all the toil that has been 
expended. Excepting the cases of gra.sses and cereals, the seeds 
of most of the plants cultivated on the farm contain two seed- 
leaves — or cotyledons, as the botanist terms them. As a rule these 
cotyledons, in the course of germination, free themselves from 
the seed-coat and appear above ground as the first green leaves 
of the young plant or seedling. No one is more familiar with 
cotyledons than the turnip-grower, for he is aware that it is just 
at the critical stage when the seed-leaves have appeared above 
ground, and before the subsequent leaves have begun to expand, 
that the plant falls a victim to the rav.ages of the turnip “ fly.” 
If by any means the plant is hurried from the “ smooth-leaf ” 
into the rough-leaf stage it usually escapes, for the dainty palate 
of the “ fly ” disdains the rough leaf. The smooth leaves, in fact, 
are the cotyledons, and it is precisely when the turnip crop is in 
this mustard-and-cress salad stage that the “fly” pounces upon it. 
No terms, perhaps, are better known to farmers who grow turnips 
and swedes and rape than “smooth leaf” and “rough leaf,” and 
the fact that these terms are applied to the leaves of one and the 
same plant at once suggests that the plant produces leaves which 
are not all alike. Sir John Lubbock asks the questions, why are 
not the leaves of a plant all alike, and why should they differ 1 
“ The germination of plants,” it is remarked in the preface, “ is 
certainly not the least interesting part of their life history, but it 
has not as yet attracted the attention it deserves. The forms of 
cotyledons, and the fact that they differ so much from the subse- 
quent leaves, had of course been attended to more or less fully in 
botanical works, but no explanation had been offered, and Klebs 
in a recent memoir expressly states that the problem is still an 
enigma ” 
It is quite possible that people who have never taken the 
trouble to examine a seedling plant may entertain the idea that 
all cotyledons, or seed-leaves, to whatever plant they may belong, 
are pretty much alike. This, however, is far from being the case. 
Some cotyledons are narrow, as in the Fennel and Sycamore ; some 
are broad, as in the Beech, Acorn, Bean, Cabbage, and Pink. How 
many people have noticed that in the Mustard, eaten as a salad, the 
two cotyledons (fig. 1) are unequal ? The same is the case in the 
Cabbage and Radish. In other species there is inequality, not 
between the two cotyledons, but between the two sides of the same 
cotyledon, as in the Laburnum and the Lupin. Though most cotyle- 
dons are entire, in some cases they are more or less lobed, — 
slightly lobed, perhaps, as in Mustard ; markedly three-lobed, as 
in Cress ; five-lobed, as in the Lime-tree. 
The following remarks on seeds occur on page 56 of vol. i. : — 
“ As regards the size of seeds, if we could imagine a state of things in 
which every seed grew and attained maturity, then to keep up the number 
of any given species existing at the time, it would be sufficient if each plant 
produced but one or two .seeds during its whole life. There is, however, an 
