154 
The Pogoniris Section 
Spathes, i — 2^ in. long, 1 — 2-flowered. 
Pedicel, short. 
Tube, short at first but about 1 in. long when the flower is fully expanded. 
Falls, bearded, with reflexed blade, either blue purple or yellow. 
Standards, blue purple or yellow. 
Observations. 
This small but very floriferous Iris is not apparently in cultivation. Specimens of it are re- 
markable for the close growth of the shoots, which are enclosed at the base in white membranous 
sheaths ; the latter are surrounded with the fibrous remains of old leaves. The root fibres are noticeably 
thick, for such diminutive plants. The only other species with which /. tigridia may be confused is 
/. Potanini, which however always has blunt leaves cased at the base in very abundant fibres, while 
the leaves of /. tigridia taper gradually to a fine point. (See Fig. 18, p. 153, and Fig. 19, p. 154,) 
There seems to be no good ground for separating /. pandurata Maxim, from /. tigridia. Maximowicz 
says (B. A. P. l.c.) that his I. pandurata is similar to /. tigridia but distinguished by its two-flowered 
spathes. The only specimens he quotes were gathered by Przewalski in Western Kansu. An examination 
of plants (K) from this same locality collected both by Przewalski and Potanin show that of seven stems 
on one plant only one has two flowers, all the others having a single-flowered spathe, while another 
plant has equal numbers of 1- and 2-flowered spathes. Another noticeable feature is that the perianth- 
tube lengthens out very late. When the flower buds appear from the spathes the tube is only £ in. 
long but it rapidly grows to as much as an inch in length. Herbarium specimens are therefore apt to 
be more than usually misleading. 
Nothing is known of the cultivation of this Iris but its floriferous character would make it a desirable 
introduction and it would probably prove to be quite hardy. 
/. Potanini 
(Fig. 19) 
Maximowicz in B. A. P. XXVI. pp. 528 and 537 (1880). 
M£l. Biol. X. p. 721 (1880). 
Baker, Hdk. I rid. p. 27 (1892). 
Synonym. 
Fio. 19. 
[N.B. 
I. Thoroldi , *Baker in Hook. Ic. Plant. XXIV. L 2302 (1894). 
Baker ex Hemsl. in J. L. S. XXX. pp. 118, 129 and 139 (1894). 
Distribution. North-western China and Thibet, where it is 
found at a height of 17 — 18, 000 feet. 
West Kansu, 1886, Potanin (K) (B) (E). 
Western China, 1908, Forrest, no. 2404 (K). 
Szechuan ; between Batang and Litang, 190-, Bonvalot 
et le Prince Henri d’Orl^ans (P). 
Northern Thibet, 1884, Przewalski (K) (V) (B). 
N.E. Thibet ; Si-an-si-bei, 1904, Filchner, no. 99 (B). 
Central Thibet, 1891, Thorold (K). 
1892, Rockhill (K). 
18 — , Welby and Malcolm (K). 
Diagnosis. 
/. Polatiini Pogoniris ; /. tigridiae valde similis sed folia 
obtusa. 
Description. 
Rootstock, even smaller than that of I. tigridia, but 
otherwise of similar growth. 
Leaves, 1 — 3 in. by £ in., ribbed, with a rounded blunt 
end, not pointed and tapering as in /. tigridia. The mem- 
branous sheaths at the base are present but almost concealed 
in a dense mass of curly fibres. 
Stem, 1 in. long, 1 -flowered. 
Spathes, membranous, i| — 2 in. long. 
Tube, slender, becoming gradually wider in the upper 
part, i£ in. long. 
Flowers, small, bearded, either yellow or purple. 
Maximowicz apparently knew only the yellow-flowered form but Przewalski, 1884 (K), has 
I. Potanini from a herbarium specimen , 
very slightly reduced. 
a purple-flowered example and so also has Potanin, 1886 (K) (B).] 
