Introduction 
3 
of the plants turned out to be a new species. This is obvious if the notes are compared with his 
published descriptions in the Gardener's Chronicle, the Botanical Magazine and elsewhere, for the 
phraseology is identical or only slightly modified. 
These notebooks have been most kindly lent to me by Miss Willmott, and I owe much to the 
insight into Foster’s methods which I have derived from the perusal of them. Unfortunately they 
have proved to contain little information that is not already available in one or other of the above- 
mentioned publications. In other words, the only cases in which a complete description of a species 
is given are precisely those in which Foster himself published the plant as new. In other cases, it is 
provoking to find a plant described by some such entry as the following, “ practically a yellow 
Notha” or "a form of tolmeiana,” because we nowhere find any definition of what Foster himself 
understood by these names. These concepts, which existed in his mind, were never recorded, and 
their loss has deprived his notes of much of their value. 
Here and there, however, the notes have given unexpected help in clearing up difficulties, as 
for instance in the case of /. masia. This was known to Foster as /. masiae, though the name 
apparently meant nothing to him. He merely recorded that he received a plant bearing this name 
from Max Leichtlin and gave an incomplete description of it, when it subsequently flowered. Two 
or three years ago I was fortunate enough to find in the Kew Herbarium an undetermined Iris, 
discovered by Sintenis near Siiverek in Asia Minor, which I recognised as being identical with 
Foster’s /. masiae. It is well known that Max Leichtlin often obtained plants and seeds from 
Sintenis and the missing link in our information was supplied by the discovery that a range of hills 
known to the Ancients as Mons Masius lies close to Siiverek. Sintenis' herbarium specimens do 
not tell us much of the flowers, but with their aid and with Foster's notes we are able to compile 
a fairly full account of this interesting species 1 . 
Except in a few cases of this sort, Foster's notebooks have been of little direct use for the 
reasons already explained, but I have endeavoured to acknowledge my debt whenever I have derived 
any information from them. 
An apology is perhaps due for the unsatisfactory state in which the accounts of some of the most 
widely distributed Irises have been left. The difficulty lies in the fact that of such species as 
aphylla , ruthenica, ensata and spuria there appear to be almost innumerable local forms, which cannot 
satisfactorily be separated when dealing only with dried herbarium specimens. Living and indeed 
growing plants are absolutely necessary and, though by diligent search in gardens, many of these 
forms can be got together, it is by no means easy to obtain a series of wild forms from known 
localities. Even when wild plants or seeds are procured, it is necessary to grow them side by side 
for a year or two before their true characters can be seen, for soil and cultivation have often great 
influence on the growth of the plants, which usually seem to grow much more luxuriantly than in 
the wild state. This is not always the case, however, for in some rich natural soils, specimens are 
to be found that are as luxuriant as any cultivated plants and which, as herbarium specimens, appear 
at first sight to be distinct from the dwarf plants that form the majority. Iris ruthenica is a good 
instance of this variability. In favourable conditions the stems produce two flowers while in weaker 
plants each stem produces only a single flower. There is, however, no ground for setting up a 
separate form or even species under the name of uniflora, when all specimens agree in the character 
of the foliage, spathes, capsule and seeds. The last are peculiar and unlike those of any other 
known Iris. It is, moreover, a curious fact that at least among the beardless Irises, each species 
has characteristic seeds by which it can readily be recognised, and we therefore seem justified in 
grouping together under one specific name the various local forms of this Iris that undoubtedly exist. 
In the same way I. ensata is very variable, but all the forms are at once distinguishable from 
all other species by the curious capsule (see Fig. 11, p. 87). The case of I. aphylla is, perhaps, 
more difficult, but, at present, it seems advisable to group together under this name all dwarf bearded 
Irises from Central Europe and the Caucasus in which the stem forks either low down near the 
ground line or at any rate below the middle. No other bearded species has a lateral branch, which 
is nearly as long as the main stem, and the change that a year s cultivation produced in collected 
rhizomes from the Caucasus makes it very inadvisable to attempt at present any definite grouping 
of the various forms of this species’. 
In the case of /. spuria some attempt has been made to separate several of the various forms, 
but it is necessarily incomplete and tentative. 
It is somewhat surprising that the professional botanist should so frequently be entirely lacking 
in horticultural enterprise. It is true that this lack of enterprise can often be accounted for by 
considerations of time and space, but yet it is remarkable that there is so seldom any opportunity 
afforded for working out with living plants in a botanical garden the problems that arise in the 
herbarium. Doubtless, the specialist is apt to attach an altogether exaggerated and entirely unjustifiable 
1 I have since found both in the Vienna and in the Paris collections further specimens collected by Sintenis with the name 
/. masia suggested by Dr Stapf, who, however, never published any description of the species. 
9 Bieberstein’s description of I. furcata makes the spathes one-flowered and the withered stem on collected plants confirmed 
this, but after a year's cultivation in my garden two flowers in a spathe were common. This instance serves to show the 
difficulty of distinguishing and grouping the local forms. 
1 — 2 
