i6o 
THE ESSEX NATURALIST. 
Much interest, however, may be found in these often abused 
surburban conifers when we get to know more about them and 
can picture them, at least in imagination, in their native haunts. 
I have made a list of those I have seen in the gardens of Leyton- 
stone, Wanstead, Woodford, and Chingford, as far as I could 
make them out from the road, and find they number twenty- 
seven species. Probably this list is far from complete, and I 
should be grateful to anyone who would help me to add to it. 
Considering that conifers demand pure air, if they are to thrive, 
I think our district has not done badly. 
But it may well be asked “ what is a conifer ? ” 
Conifers belong to the division of seed'-bearing plants, called 
Gymnosperms (from the Greek gymnos naked, sperma seed) or 
plants with naked ovules, as contrasted with the true flowering 
plants or Angiosperms (Greek aggios a little box, sperma seed), 
in which the ovules are in a closed box, or ovary, the result being 
that in Gymnosperms the pollen grains are carried by the wind 
direct to the ovules, and in Angiosperms they can only reach 
the ovules by penetrating the stigma of the ovary. 
Gymnosperms have an extremely ancient ancestry, dating 
back as far as the Carboniferous formation. 
Modern Gymnosperms are divided into four great classes :— 
Cycads, Gnetales, Ginkgoales and Conifers. 
The Cycads, which in a past geological period formed one 
of the most important groups of plants on the land surface of 
the earth, are now reduced to a few genera and species growing 
chiefly in the southern hemisphere. They are mostly short, 
stout-stemmed plants, with very large fern-like leaves, and with 
large terminal cones of either male or female flowers. None of 
them are capable of growing out of doors in English gardens, 
and so, although from the point of view of relationship they 
are extremely interesting, we need not refer to them further 
here. 
The Gnetales are a still smaller group of curious plants, con¬ 
taining three genera, which differ much in appearance from each 
other and from other Gymnosperms ; in some respects they 
show affinities with true flowering plants. 
The Ginkgoales contain a single genus and species, Ginkgo 
biloba, the Maidenhair tree. Until recently the tree was 
regarded as a conifer, and this is my excuse for speaking of it 
