106 EVANS—EFFECT OF ENVIRONMENT ON THE 
capsule, where present, were in this way situated immediately 
below the point of origin of the foliage leaves, the primary root 
having bored its way through these relics of the parent plant in 
its elongation (Fig. 2). On the other hand, the seedlings germi- 
nated this spring, while corresponding in other respects with the 
foregoing description, showed the remains of capsule and perianth 
as though carried downwards for some considerable distance by 
the primary root in its growth (Fig.1). How was this difference 
to be accounted for ? 
Upon closer observation it was noticable, in the case of the 
seedlings in which the remains of the flower parts were situated 
some distance from the leaves, that what I had at first taken to 
be a portion of the primary root lying above the remains of these 
flower parts—which had previously surrounded the seed—was 
thicker and more transparent than the undoubted primary roots 
of the seedlings in the other series, and differed in the same 
respects from what I had thought to be its continuation beyond 
the perianth segments envesting it. The probability of its being 
an elongation of the short hypocotyl described by Laurent (1) 
then occurred to me; and a consideration of the type of germin- 
ation which, according to him, is common to all the Juncacee 
(and which I had already observed myself in the case of /uncus 
glaucus, Sibth.), as well as other points to be mentioned later, 
convinced me that this was the truth. A short account of those 
features of this germination which bear upon the present case 
may help to make my point clearer. 
Owing to the elongation of the cotyledonary axis on growth 
commencing, the embryonic primary root is thrust outwards 
through the micropyle of the seed. The cotyledon continues 
still to elongate, bringing the root pole into contact with 
surrounding material, and later, when the plantlet has become 
firmly attached to the rooting-medium, growing upwards as the 
first green leaf of the plant, and carrying on its apex the seed. 
Immediately the rudimentary root comes into touch with any 
surface, a collar of long root hairs appears at its upper limit, 
which serve to anchor the young plant and allow the primary 
root the leverage necessary for the burrowing operations it has 
soon to commence. This fixation of the starting-point of the 
root before its elongation is what I wish to emphasise, because, 
