ANALYTICAL KEY 
TO THE SUBDIVISIONS OF THE GENUS IRIS. 
N.B. A Key to the species in each subdivision will be found at the pages 
t Rootstock bulbous. 
( Rootstock non-bulbous. 
Rootstock a simple bulb without persistent roots. 
Rootstock a bulb with fleshy roots persistent in the resting season. 
Rootstock a bulb with smooth, membranous outer coats. 
Rootstock a bulb with netted outer coats. 
Rootstock a corm with shaggy, netted coats. 
Rootstock neither a bulb nor a corm. 
Rootstock a minute flattened rhizome, hardly more than a growing point, surrounded 
by a thick mass of fibres and having a number of fleshy persistent roots 
attached to its base. 
Rootstock a rhizome. 
5 - 
Outer segments (falls) crested. 
Outer segments (falls) not crested. 
i Outer segments (falls) bearded with multicellular hairs. 
' Outer segments (falls) unbearded or with a pubescence of unicellular hairs. 
7 - 
Seeds with a conspicuous, creamy-white, circular aril. 
Seeds without any conspicuous aril. 
Aril conspicuous, often nearly as large as the seed itself ; flowers not appearing 
until the leaves are practically full grown. 
Aril not so conspicuous, much smaller than the seed ; flowers appearing when 
the leaves are still quite short. 
Stem i -headed, I -flowered. 
Stem i -headed, 2 — 3-flowered. 
Inflorescence 
no. 1 1 ) ; 
I nflorescence 
a regular raceme, seeds conspicuously winged (cf. Plate XLVIII. 
flowers fugitive and twisting spirally as they wither. 
not a regular raceme, seeds not conspicuously winged. 
indicated. 
1. 
3 - 
2. 
The Juno Section 
(see p. 187). 
The Xiphium Section 
(see p. 210). 
The Reticulata Section 
(see p. 220). 
The Gynandriris Section 
(see p. 229). 
4 - 
The Nepalensis Section 
(see p. 184). 
5 - 
The Evansia Section 
(see p. 98). 
6 . 
7 - 
10 . 
8. 
The Pogoniris Section 
(see p. 135). 
9 - 
The Pseudoregelia Section 
(see p. 129). 
The Oncocyclus Section 
(see p. 107). 
The Regelia Section 
(see p. 123). 
The Pardanthopsis Section 
(see p. 96). 
The Apogon Section 
(see p. 18). 
D. 
3 
