11 EANUNCULACE^ 49 



growing to a height of 20 to 30 feet. It is a southern 

 form, extending to the Mediterranean, and not reaching 

 to our northern counties. It is not regarded as a 

 native of Ireland, but is naturahsed there. It flowers 

 in July and August. 



Thalictrum 



The species of this genus are also, as a rule, pollen- 

 flowers. Their conspicuousness is due to the numerous 

 stamens. In one species the anthers are yellow; in 

 T. aquilegifolium of Southern Europe they are violet. 

 The species are widely dispersed over the temperate and 

 colder regions of the northern hemisphere. They are 

 variable, and botanists difi'er much as to the number. 

 The most distinct British forms are T. alpinum, 

 T. minus, and T. Jlavum. 



T. alpinum is a graceful little plant 4 to 10 inches 

 high. The leaves are biternate and glaucous beneath ; 

 the flowers form a drooping, simple, terminal raceme. 

 The sepals are slightly purplish. The pollen is probably 

 carried by the wind. It is probable that this species 

 once occupied most of the northern hemisphere south 

 of the great glaciers. It grows on the mountains of 

 Wales and Scotland and all over the northern hemi- 

 sphere as far north as Nova Zembla, descending to 

 lower levels towards the north. In Ireland it is very 

 rare. 



T. minus. — In this species also the pollen is probably 

 wind-borne, but the flowers are sparingly visited by flies, 

 beetles, and bees. The flowers are mostly drooping. 

 The leaflets are roundish. It occurs from the Hima- 

 layas to Greenland and North Africa, but does not 

 ascend so high or reach so far north as T. alpinum, and 

 prefers calcareous districts. 



T. flavum. — In this species, on the contrary, the 

 flowers are mostly erect, and the pollen is carried by 

 insects, especially flies. It is 2 to 4 feet high, and not 

 uncommon along the banks of streams. The stem is 

 erect, branched, and furrowed. The leaves are bipin- 



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