428 BRITISH FLOWERING PLANTS chap. 



and they close soon after mid-day. In wet weather they 

 are almost cleistogamous. 



J. trifidus. — The female condition lasts 2 days, the 

 whole flower-life is probably 4. 



LuzTJLA (Wood-rush) 



This genus has softer and more grass-like leaves, often 

 with a fringe of hairs. We have five species — three with 

 flowers in panicles, two in compact heads. 



L. campestris. — The perianth segments are very 

 pointed. As soon as the bud begins to open the three 

 stigmas push out, and soon wither. Several days (5-9) 

 then elapse before the flower is completely open, and 

 another, making 6-10, before the anthers are ripe. The 

 flower remains fully open for about 36 hours. From the 

 long interval between the withering of the stigmas and 

 the ripening of the anthers, it is evident that the flower 

 can never fertilise itself. 



L, pilosa. — In this species the stigmas remain fresh 

 for 4-5 days, during which the perianth is only partially 

 open. It then expands for some hours, the anthers 

 open, and finally the flower closes. 



L. sylvatica. — This is the largest of our species. 

 The female condition lasts one or two days. Then 

 the flower and the anthers open. In this case, how- 

 ever, they do so while the stigmas are still fresh. 



L. arcuata is an Arctic and Alpine plant found in 

 Britain only on the Scotch alps. 



EEIOCAULEiE 



Small herbs with a dense tuft of narrow grass-like 

 radical leaves, and a scape bearing a dense head of 

 minute sessile flowers, subtended by an involucre of 

 bracts, and suggesting a Composite. It is almost 

 restricted to the warmer parts of the earth ; it is 

 represented in Europe by the following species. 



