THE MONOCOTYLEDONES 2033 



owing to the later development of the branched stigma. It is often to be 

 noticed in gardens that birds, especially sparrows, bite off the flowers m 

 larcre numbers. Whether this is to obtain the nectar is not known but it is 

 remarkable that yellow rather than white or violet flowers generally suffer 



most in this way. r , 11 ^ ' 



C sativa is of economic importance because of the orange-yellow dye 



which is obtained from the dried stigma and sold as saffron. It is used in 



flavouring, in colouring dishes and in liqueurs. 



The genus Romulea includes about fifty species occurring m Europe 



and especially in the Mediterranean region. Several are in cuhivation while 



R. columnae is found rarely in the west of England and the Channel Islands. 



II. Iridoideae . 



The rootstock is either a rhizome, or a corm, or a bulb, generally with a 

 leafv stem ending in an inflorescence, the spathes of which are two- to 

 several-flowered. Leaves usually in two rows. Flowers actinomorphic, 

 perianth in two whorls of different form. , • , ,u 



Included in this sub-family are about forty-five genera ot which the 

 more important are /m, Moraea, Tigridia, Sisyrinchium and Lihertia. 



The largest and most important genus is /m, with about 200 species 

 widely distributed through north temperate regions. Two species, 1. 



Fig. 1972. — his foetidissima. Gladdons. 

 Flower. 



pseudacona (Yellow Flag) and /. f"^''''"-"'" '^'^^J^^ Ta^I^tTd 

 (Fig. 1972), occur in Britain, but many other spec.es, vanefe. ana 



